1) Take your time!
There is no reason to rush the investigation.
Look around, chat with your robot, try to walk everywhere - you'll never know what interesting things might come up. There are only very few places and events in the game which give you an actual timelimit for investigating.

2) Look closely!
- There are often artefacts hidden just lying about in the strangest places, but to get an investigation prompt you might need to get closer first or look at an item more than just once - sometimes there will be no marker at all and you can just walk into a hidden find.
- Also look up once in a while.
- You wont see any investigation markers while in the middle of a dialog.

3) Questions or Statements?
While you are exploring you will often be able to make a Statement or ask a question. While Statements will be available faster, the questions are often more useful and also allow for building a friendlier relationship with Six.
Statements or Questions displayed in a bright green color might give Aliya an important new idea or revelation and lead to new discoveries.
Though answering a question with another question might be considered rude as well.

4) Not answering is also an answer.
When in a dialog, and you don't like any of the possible answers to give, you can wait a few seconds and the dialog simply ends at that point. (Might not work in a few important conversations.)

5)You can change the text speed when in a hurry.
On occasion, there will be scenes with a strict time limit. It might help a lot to speed up the text display of the dialogs in the options menu on those occasions.

6) You can't go back!
Once you leave a historical site you will not be able to return to continue the investigation. So make sure you have seen all there is to see. This also holds true for the moons Maersi and Renaki, which are only possible to visit for special events.
Don't let Six talk you into leaving a place too early, it is usually better to head back to the ship manually after the full investigation instead.

7) Some artefacts can be used for more than just translating, bartering or triangulating new sites:
- daggers can be used to pry closed containers or doors open
- keys might unlock something
- tiles or sailcloth can be used to cover stuff up
there are a few more items that will have special effects in certain places.

8) While sailing you can stop your ship by using both sails at the same time.
Sometimes an interesting dialog might come up while you are on the rivers, it will be interrupted often by reaching a destination or finding a floating ruin, so to get all of the dialog you can stop your ship for a moment and then continue the sailing.

9) While sailing also don't worry, if you took a wrong turn. You'll get back on track soon enough.
And making a detour can lead you to new undiscovered floating ruins or wrecks, which all sums up to new artefacts with hints to the unexplored sites, ancient script for translating and more objects for Tapi and Huang to show to.

10) Blue dots on the navigation map...
... are floating ruins or shipwrecks. Sometimes you will be informed that one is nearby, often you will be not. So while sailing check the map regularly.

11) When looking for a new archaeological site, make sure you have visited all uncovered floating ruins and wrecks nearby first.
For some reasons you can't find more artefacts from sites you have already entered. That means after visiting a new site, floating ruins and wrecks you had sighted while sailing but not stopped at, will disapear and with them the artefacts hidden within.

12) Don't worry too much, if you are not sure of a translation.
Once you find more samples of the same word in ancient script, Aliya will tell you whether you guessed right or wrong.

13) If you get stuck...
... visit Tapi on Elboreth and show him an artefact from the site you are looking for and he might have something from the same place that helps you triangulating the site. (You don't have to trade it if you want to keep your rare item.)
Timor and Huang may also have clues for you.
You can also just sail around near the site of interest and try to find more floating ruins or shipwrecks for helpful artefacts.

14) I suggest you avoid spoilers like the plague x_x
The game lives of you investigating a thousands of years old mystery and a few newer ones.

15) If you start a New Game +,...
...your translation dictionary will carry over and you will encounter longer and more complicated sentences from the ancient script.