The guide is split in Chapters and every achievement is in chronological order to make things easier. There's a Game Credits section too because the last part of one of the achievements is in the credits, so don't miss it.
There is also an achievement for not using any hints and the hint system is in your phone, so be careful when you're messing with it. The game isn't hard at all so you probably won't need hints but, if you get stuck, leave a comment and I'll help you out.
It is possible to get all the achievements in one playthrough with a little of save management. Follow my guide and you won't have any problems.

Performing Monkey Hat

Story related and can't be missed - Depart for Venice and you'll get it.

Stick it to the Man

Missable - Save your game before talking to Detective Brunetta in Murder Bridge. Talk with him and, when he asks you about your business with the case, answer with "That's none of your concern". Then, when he asks you if you've been hired by Cardolo, answer with "That's really none of your concern". You'll get the achievement at the end of the conversation.

Cooperate with the Authorities

Missable - Load the game you saved before talking to Brunetta, but this time answer with "I'm not here to find her killer" and then with "No, it wasn't Cardolo". You'll get the achievement at the end of the conversation.

Charming young man

Missable - After talking with the Detective in Murder Bridge, knock at the green door that's on the right. Analyse the old lady to notice that she's missing a necklace. Talk with her, then do a web research on Catarina Felone with your phone. Go to Barozzi's Antiques and examine the Murano necklace in the necklace case. Buy it and go back to the old lady to give her the necklace and get the achievement.

A Compelling Biography
Story related and can't be missed - You'll get the achievement once you've collected all the 13 Bianca Cardolo data points.

Mingle with the Locals

Missable - Talk with Hasim, Saa and Ammon in the bar, then to Layla in the Hostel.

One Good Deed Deserves Another

Missable - After beating Hasim at darts, he'll give you some informations about Masri. Save the game here and exit the bar. After the cutscene, move behind the dumper and then use your gun with the thug on the fire escape. Select "Take David" when the game lets you choose what to do with him and you'll get the achievement.

He'll Walk It Off

Missable - Load the game saved for One Good Deed Deserves Another and select "Leave David" when the game lets you choose what to do with him to get the achievement.

Muuuubius (1 of 4)

Missable - To get this achievement, you have to find 4 pink cows and click on them. The first one is in David's Hostel room, on the bed post of the bunk bed.


The Bodyguard

Story related and can't be missed - You'll get this achievement after telling to David why you want to hire him.

It Belongs in a Museum!

Story related and can't be missed - You'll get this achievement once you've solved the Canopic Chest analysis.

Muuuubius (2 of 4)

Missable - The second pink cow is on the post of the left newspaper stand outside Rector's Antiques.


The Ultimate Boyscout

Story related and can't be missed - You'll get the achievement as soon as you reach Malachi's balcony.

Mind Your Own Business

Missable - The day after being saved by David, you'll be in your bedroom. Save the game and leave the room. When the game lets you choose what to say about your pills, select "I don't owe you an explanation." and you'll get the achievement.

Medical Needs

Missable - Load the game you saved for Mind your own business and select "You want to know what pills I take?" during your conversation with David to get the achievement.

Knock-Knock

Missable - Right at the beginning of the chapter, talk with David and keep selecting the "Joke" option until you get the achievement.

Muuuubius (3 of 4)

Missable - The third pink cow is inside the trash can found in the Bibliotheque Nationale de France.


Caffeine Addict

Missable - After having talked with the librarian, go to the La Belle Eiffel Hotel and ask the barman for a coffee, then throw it in the trash bin to your right. Do it 2 more times and you'll get the achievement.

An Eye for Antiques

Missable - You need to analyse all the objects in Alfonse's Home that have the brain icon. Here is the complete list:

• Vase
  
• Clock
  
• Small mirror
  
• Sculpture
  
• Gold urn
  
• Couch
  
• Globe
  
• Bookcase
  
• Small clock
  
• Mirror
  
• Small cabinet

Follow the Money

Story related and can't be missed - Pick up the accounting ledger from the safe in Alfonse's Home and talk about it with Caroline at the Le Chateau Campagne to get the achievement.

A Mystery Man

Missable - Once you've analysed Caroline, you'll go back to the Hotel and talk with David. Choose to tell him everything and you'll obtain his last data point. Analyse him with your phone and narrow the possible matches to Captain Roderick Butler, St Armand and St Martin of Tours. Choose one of them, then click on Finish and you'll get the achievement.

Comic Relief

Missable - Go upstairs and talk with David. Keep selecting the "Joke" option until you get the achievement.

Trimming the Hedges

Missable - Go to the garden through the buffet room and pick up jasmine, hydrangea, peonias and red roses from the 4 statues to get the achievement.

It Takes the Edge Off

Missable - Give the cake to Karl and then give him some Xanas to get the achievement.

She's the One

Story related and can't be missed - You'll get the achievement once you've solved Helene analysis.

Codemaster

Story related and can't be missed - You'll get the achievement as soon as you enter the correct password on Reichart's computer.

Ladies' Man

Missable - During your conversation with Dominique, choose the following dialogues:

• When talking about Markham, select "Oh yes. Absolutely." and ""You should sue him."
  
• When talking about toxicology, select "I admire a woman with brains."
  
• When talking about her parents, select "You're better off without them."
  
• When talking about her college boyfriend, select "You must have been angry."

Also remember to bring her a whiskey bottle from Cherries on Top Bar and the earrings from Rector's Antiques. You'll get the achievement once you've solved her analysis.

By Any Means Necessary

Story related and can't be missed - Give the data key to Carter to gain his trust and you'll get the achievement.

Astronavigation

Story related and can't be missed - Examine the big dipper constellation in the tunnels and you'll get the achievement.

The Gang's All Here

Story related and can't be missed - You'll get it as soon as you find David and Helene.

Prime Asset

Story related and can't be missed - Give the rope to Malachi when you reach the hatch and you'll get the achievement.

Elementary, My Dear Watson

Missable - If you didn't use any hint, you'll get it during the last cutscene.

Muuuubius (4 of 4)

Missable - The last pink cow is in the credits, in the hands of a frightened Rector.