This guide may be outdated, as it was created around the time of the Carnelian update when Sunless Sea was in early access. While it has since been updated, some of the information in this guide may no longer apply.

As you probably know, in order to get the official book as well as the list of colours, you must talk to the First Curator in Venderbight. Simply go through the options until he gives you what you need.

To complete this colour, you will need either a Lump of Blue Scintillack or an Apocyan Chess Piece. The Lump of Blue Scinittilack can be randomly found when exploring the Wisp-Ways of the Mangrove College. Another method to get one is to giving "Port Report: London" to the Brass Embassy, but this can only be done on when the Iron Republic Days are at 15. You can also get one by stealing the Rat-star from Pigmote Island, but doing so may have dire consequences.
Getting the Apocyan Chess Piece is much more tedious, however. It is acquired from Port Cecil after completing the Principles' of Coral's somewhat long quest and not throwing the game at the end. Make sure you don't sell it, as you'll only get a measly 100 Echoes.
Take either your Scintillack or your chess piece to the Curator and you will be rewarded with a Captivating Treasure.

For this colour you will need a Ray-drenched Cinder, which can only be acquired by propogating 7 islands with Docile Blemmingans. To acquire blemmingans, you have to go to the Uttershroom with Firkins of Prisoner's Honey, one for each blemmingan you need. Then you must go to suitable islands and you should have an option to propogate the island with a blemmingan. Generally speaking, the island in question should not be hard or rocky, cold, or already be inhabited by blemmingan.

Suitable locations include:

• a Light-Ship -- Note: you will become unwelcome on all light ships, unable to turn in Recent
• News or buy Fuel.
  
• Abbey Rock
  
• Adam's Way -- Note: causes you to end your stay there.
  
• Aestival
  
• Empire of Hands -- Note: can negatively affect progress once you're helping with the Zeppelin.
  
• Gaider's Mourn
  
• Godfall
  
• Hunter's Keep
  
• Irem
  
• Khan's Heart
  
• Khan's Shadow
  
• Mangrove College -- Note: negatively affects multiple events on the island.
  
• Nuncio -- Note: gives you one Deliverable Post.
  
• Pigmote Isle - Note: militant Cavia knights may use it as a practice dummy
  
• Polythreme
  
• Port Carnelian
  
• Quaker's Haven (on Mutton Island)
  
• Saviour's Rocks
  
• Shepherd Isles
  
• Station III
  
• The Chapel of Lights
  
• The Fathomking's Hold -- Note: You will gain 1 Drowning-pearl.
  
• The Iron Republic -- Note: this will result in a net gain of +1x Docile Blemmigan.
  
• The Isle of Cats
  
• The Salt Lions
  
• Varchas
  
• Venderbight
  
• Visage

If you try to drop off blemmigans in the following ports you will lose the blemmigan and gain nothing.

• Mount Palmerston
  
• Demeaux Island
  
• Port Cecil
  
• Chelonate
  
• Kingeater's Castle -- A note will appear in your Journal ("Not Kingeater's Castle"), but you will not gain a Propagation point.
  
• Grand Geode

If you try to drop off blemmigans in the following ports, you will keep the blemmigan, but you gain no Propagation point.

• Avid Horizon
  
• Codex
  
• Cumaean Canal Staging Area
  
• Frostfound
  
• Khan's Glory
  
• Whither
  
• Wisdom

After you have propogates 7 islands, return to the Uttershroom, and you will be given a Ray-drenched Cinder. Give it to the Curator for a Captivating Treasure.

For Gant, you will have to either get a Weeping Scar, a Star-Shell, or The Figurehead of the Eater of Names.
The Weeping Scar is only acquired at the Nightmare Well at the Chapel of Lights, and is probably the easiest and safest way to obtain Gant. First off, you will need to have Nightmare Strength 1 or more, which can be contracted by returning to London with 50 or more terror, with higher terror increasing the chances of a nightmare. On this occasion having more than one is better, as you may struggle against your nightmare whilst at Zee and win, which will decrease its strength, potentially removing it entirely if you only had 1 Nightmare Strength. You will also need to be Unaccountably Peckish, which can be acquired either by choosing "Attend a service at the Chapel" (You only need to do it once, but it will cost you 5 supplies and you must pass a simple Pages challenge) or it can be randomly acquired while choosing "Eat of the Chapel's Bounty". Both of these actions are performed at the Chapel of Lights. Then you must choose "Give a Nightmare to the Well", which will reduce your nightmare strength, give you 1 wound, and the Weeping Scar.
As far as I know, the Star-Shell can only be obtained at Frostfound. While I cannot remember the exact details as I have only been there once, I do remember that all my statistics were decreased, my Terror increased well past 90, and I suffered Salt's curse. It is an extremely risky move and should only be pursued as a last resort, or if you're feeling lucky.
The Figurehead of the Eater of Names is, as the name suggests, obtained by defeating the Eater of Names. It is generally encountered somewhere near the Chelonate, but is still quite rare. Stay away from it's front at all costs as it has two forward weapons that can shred apart an unwary sailor's vessel, but be cautious as it also has an aft weapon. When it is defeated make sure you pick the "Seize its figurehead" option, otherwise you will not get it's figurehead. The Eater of Names is actually not a unique enemy and can respawn, so you can get more than one figurehead.
Take your item of choice to the Last Curator for 7 Secrets and 1 Lamentable Relic.

For Irrigo you will either need an Eyeless Skull or a Colossal Fluke-Core.
To obtain the Eyeless Skull you have to go to Godfall and explore the Citadel. You will need 5 or more Foxfire Candles (I managed with 10), and a lot of skill and luck. You may suffer wounds and die. When you finally progress to the end of the Citadel, you will acquire the Eyeless Skull needed for the colour. The skull can also be used as a mascot, giving +4 Veils but -2 Mirrors. Apparantly the skull can also be acquired from the Magician's story.
A Colossal Fluke-Core is obtained from defeating a Lorn-Fluke, which can be extremely difficult depending on your weapons and ship. It has 2 attacks: It has a ram attack which does substantial damage, and a ranged attack which does low amounts of damage but increases your Terror by 10. Use extreme caution if you decide to fight these things.
Take either your Eyeless Skull or your Colossal Fluke-Core to the Curator for a Captivating Treasure.

For this colour you will need the Hunter's Eye, sometimes found at the Avid Horizon when you have x77 Fragments or more. To my knowledge there's nothing more to it than that. Take it to the Curator for a Hunting Trophy and a Captivating Treasure.

For this one you will need Violant Ink, only obtainable either from the Empire of Hands or a random event in Khan's Heart.
To get it from the Empire of Hands you can trade it for a Firkin of Red Honey, which is significantly more expensive to acquire than the method at Khan's Heart, but also a lot more reliable as it isn't based on luck. To get the honey itself you will have to do several odd jobs at the Isle of Cats, including transporting some vials of Red Honey to London. Be cautious as this will raise your suspicion, and being found in possession of Red Honey has it's consequences. Eventually you'll be given a Key to the Cage-Gardens where you can buy a single Firkin of Red Honey when Something Awaits You in Port for 600 Echoes. Afterwards simply sail to the Empire of Hands and and give them a Gift of Red Honey to obtain the Violant Ink.
For Khan's Heart you will probably need the Nephrite Ring for it to occur, which means buying lots of sacks of Darkdrop Coffee Beans and giving them to the people at Khan's Glory. When you do encounter the event you can simply buy it for 77 Echoes.
Give it to the Curator for yet another Captivating Treasure.

To acquire Viric you will either need A Mirrorcatch Box Full of Very Angry Dream-Snakes, A Mirror-Charm, or A Phantasmal Encounter, 189-, Captain ------.
A Mirrorcatch Box Full of Very Angry Dream-Snakes is obtained reliably from the start of the Tireless Mechanic's quest. To obtain it you will need to create a Serpent-Trap at Hunter's Keep, which depending on the state of Hunter's Keep, will need either:

• 1 Clay Man, Marked for London
  
• 1 Memory of Distant Shores
  
• 1 Tale of Terror!!
  
• 1 Zee-ztory
  
• 1 Empty Mirrorcatch Box

OR

• 1 Clay Man, Marked for London
  
• 5 Supplies
  
• 1 Empty Mirrorcatch Box
  
• 1 Foxfire Candles

6 Clay men are obtained for free from Polythreme and are generally sold to London, but you can only have one batch at once. One clay man is used when creating a Serpant-Trap but this does not affect your ability to sell the others.
Mirrorcatch Boxes can be purchased from Khan's Shadow for 250 Echoes or Khan's Heart for the same price, but only with the Nephrite Ring. It can also be purchased from Irem for 3 Secrets, if I remember correctly.
Be aware that you need three or more crew to be able to obtain the box of snakes, and there is a chance you will loose one.

You can get the Mirror-Charm from Varchas. As far as I know Varchas cannot be obtained on your first visit there, and can only be visted when something awaits you in port. If I remember correctly, you must first suffer from Dreams of Smoke by sleeping in a room with mirrors and then talk to the priestess who will give you a Mirror-Charm.

A Phantasmal Encounter, 189-, Captain ------ is by far, the most difficult one to obtain, and is based soley on luck and nothing more. Attempting to acquire it at all is generally ill-advised as it is both much easier to acquire either of the alternatives and also has no use money-based or otherwise.
Firstly, you must encounter one of many random events in Venderbight called 'The Serpent-Image'. You be presented 3 options; an easy pages challenge, a hard pages challenge, and third option to leave the event. The pages challenges have the same outcome, so I recommend you take the easy one. You will then be given a "Fingerking's Footsteps". After that, you must encounter the same event a second time, and progress through it as you did last time [although the pages challenge may not be there, the text should be identical]. You will then encounter Déjà Vu, with two options, one of which being a very hard pages challenge, which you must succeed. If you don't you will have to encounter the event all over again. If you do, you will be rewarded with "A Phantasmal Encounter, 189-, Captain ------".
Give your whatever curiosity you obtained to the Last Curator for a Captivating Treasure.

After witnessing the Curator's End, you will be free to choose one of a selection of rewards:

Whilst the boat is a definite upgrade from the starting ship, it is not that great in itself; its main attraction is the boosts it gives to your stats, as it gives +10 to Hearts, Veils, and Pages. Choose this if you're desperately in need of a new ship or better statistics.

With the other treasures you acquired, you'll have 13 of these, or less if you sold them or converted them into heirlooms. An excellent choice, as they can be sold to the University for 1000 echoes each, making this choice a good option for those who want to make money.

Choosing this option is generally ill-advised, unless for whatever reason you're having a lot of trouble obtaining Secrets or are simply in dire need of them. Pick it if you desperately need permenant stat boosts, or if Irem has something you want.

A curiosity and a mascot, this is a bold choice; It will decrease your Hearts by 2, but increase your Mirrors, Veils, and Pages by 3 each. Good for those who want a boost to their stats, but don't want a different ship.

That probably concludes everything, you now have your reward. Thank you for reading my guide. I should probably stop making these at 2am.
Some information and imagery was taken from http://sunlesssea.gamepedia.com/.