There are 9 conversation related achievements. Talk with the following characters about everything. The achievement should pop once you say your goodbyes.

• Gretchen
  
• Trude
  
• Leni
  
• Baron
  
• Barbarossa
  
• Sailorman
  
• Alpinist
  
• Lessing
  
• Madonna

The by far most obnoxious achievement is "You Remind me Today of a Small Mexican Chihuahua" which requires to get 35 dictaphone entries. Not only because you can simply miss some of those but mainly because you can screw this up easily by doing the correct things BEFORE you got the entry. Here is the number you should have after each chapter (you can check it in the inventory) and the entries you need to be careful about. Always make sure you have the number of entries you need before making big steps towards the next chapter.

Prolog: 6
All but one is automatic and the last one you can get in Chapter 1

Chapter 1: 18
Warning 1: as soon as you see a "cat" in a tree, tell Beverly about it before you do anything else
Warning 2: if something breaks apart in front (and because) of you, tell the world about it before you try doing something with it.

The end of chapter 1 is near once you got everything to fix what was broken at the beginning of the chapter.

Chapter 2: 19
No issues here, the only entry in this chapter is automatic

Chapter 3: 24
Just look at everything and you'll be fine. 3 manual entries: The first where you arrive, the second where something big is blocking your progress and the third right after.

Chapter 4: 35
Warning 1: Well, thats a lot of crows on a tree. Better make a record first before doing anything else.
Warning 2: Always record local flora before picking it.
Hint: About two things you already did recordings of you know a lot more now, so do them again.

Other things to be on the lookout for:

• In Trüberbrook people deal with things themselves. No need to get the authorities involved. Or report things.
  
• Its amazing what you can learn from the newspapers. There is one in every chapter after the prolog.
  
• One coin and two things to do with it... use the "Alt+F4 / reload" trick after the first coin related achievement pops up.
  
• It takes a lot of trial and error to figure out how to open a door. Immediately when you have solved the puzzle Alt+F4 out, reload and do it right the first time.
  
• Are you sure you have asked Lazarus enough times about Doppelkopf? (even if its the same questions over and over again)
  
• A concert is a good place to light some fireworks in the sky. Be generous with your clicks.

... use these excellent guides

Trüberbrook Komplettlösung & Erfolge (German) - courtesy of @knuddelangel

Achievement-Guide (English) - courtesy of @orgua