*Click to enlarge.

Find everything in the game
➜ With this guide, you can get this achievement in no time!
Let's get it started!!

Beat the game with 3 thumps, without upgraded sword, shield, or armor
➜ I suggested you to get this on your second playthrough to shorten the length of times that requires for this achievement since you're already familiar with the game, dungeons, boss fights, etc. Rush through everything and you should get it within 3 to 4 hours.
The only biggest challenge to get this achievement probably the final boss fight. Prepare spare-thumps & some invincible trail mix just in case.

Party in the Rave Cave for 11 minutes and 12 seconds
➜ Stay in the cave for 11 minutes and 12 seconds that's all you need for this achievement!
Let's dance!!

Complete the Love Note quest
➜ Get the Love Note from Tree Trunks (cave 3) and deliver it to Mr.Pig (cave 1). Once you done it, you can buy spare-thumps which will refill your health for 50 pennies.

Complete the Cinnamon Fun! quest
➜ He is blocking your way on the brigde and you need Poot to get pass him. You can find it at the Medium butt rock, prepare an empty baggy. (Location on map)

Complete the Trading Game quest
➜ First, you need to get Jake's grabby hand at Song temple.
➀ Go to the Video store, use the grabby hand on the shelf and take the Heat signature.
➁ Next, trade the Heat signature with Shelby for Mind games.
➂ Go to cave 7 where the Ice king at. Give him the Mind games and get Fan fiction in return.
➃ Trade the Fan fiction with Coal man for Honey energy drink, he is at cave 9.
➄ Go to the Rave cave, give the Honey energy drink to Party pat and receive Bug milk from him.
➅ Finally, give the Bug milk to Nightosphere demon and quest completed!

Complete the Door Repair quest
➜ The quest NPC Wizard thief is in cave 6. You need to find 5 Wooden boards to complete the quest. (Wooden board's location refer to map)

Complete sword training
➜ You need to gather 20 Gum globes to learn the ultimate sword skill from him, the Rattleballs. (Gum globe's location refer to map)

Find all thump shards / spare thumps
➜ There are 18 thump shards and 3 spare thumps in total.
(Thump shards/Spare thumps location refer to map)

Find all five baggies
➜ There are five baggies in total in the game.
(Baggy's location refer to map)
➀ Inside the chest in the cave just outside of the castle.
➁ Buy it from the Choose Goose's shop for 20 pennies.
➂ Reward from the pot breaking record challenge.
➃ Reward from Wizard thief after you completed the Door repair quest.
➄ Reward from completed Starchy's graveyard fun run.

Find every Gunter cave
➜ They are everywhere but you can find them mostly inside the cave.
(Gunter's location refer to map)

Complete the tutorial
➜ Hmmm, complete the tutorial.

Complete the Song Temple
➜ Hmmm, complete the Song Temple.

Complete the Dream Temple
➜ Hmmm, complete the Dream Temple.

Complete the Fear Temple
➜ Hmmm, complete the Fear Temple.

Choose Lullaby Princess to rule
➜ Hmmm, choose Lullaby Princess to rule at the ending.

Choose Slumber Princess to rule
➜ Hmmm, choose Slumber Princess to rule at the ending.

Choose Nightmare Princess to rule
➜ Hmmm, choose Nightmare Princess to rule at the ending.

Chop down 999 bushes
➜ Hmmm, chop down 999 bushes.

Find a gum globe
➜ Hmmm, find a gum globe.

Find a thump shard
➜ Hmmm, find a thump shard.

Buy something from Choose Goose
➜ The Choose Goose's shop at the north of the map.

Use Grabby Hand on a Pie Fairy
➜ Pie Fairy can be found at certain location and inside dungeon as well.

Buy any trail mix
➜ The Witch's shop can be found at the East side of the map.

Complete the Terrible People quest
➜ Capture Tiny manticore with an empty baggy, and give it back to Magic man.

Store a Convict Fairy in a baggy
➜ Make sure you got an empty baggy before trying to catch it!

Kill a Lub Glub using Flambo
➜ Lub Glub can be found inside Fear Temple.

Beat Starchy's Graveyard Fun Run
➜ You can win this challenge easily by removing the rock and the bushes.

Talk to Stanley five times
➜ Get close to it and keep press action button. (Location on map)

Lie to Marceline
➜ Throw Jake in the water, and when Marceline asked choose Mr.Fox instead.

Receive every curse
➜ Let the enemy touch and curse you. Four curses in total, poison, confuse, freeze and big foot.

Complete the Dungeon Drama quest
➜ Once you've finished the Fear Temple, you can find the LSP at Totally freaky dungeon.

Kill an enemy after both Finn and Jake have attacked it
➜ You need Lady Rainicorn's Ring for this, can be obtained at Fear Temple.

Break the pot breaking record
➜ You need Jake's Slammy hand for this challenge.

Stun 5 enemies with a single Bananarang
➜ First, you need to upgrade your Bananarang if you haven't already. There are many places are good for this achievement after you've completed the third dungeon.
Just kite the mobs around, stun it first before you use the bananarang charging skill. You should get the achievement if you do it right.