Here is the full list of all 28 Manual Samuel achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Complete Story Mode Single Player
Complete Level 8
Didn't skip any cinematics
Complete Level 7
Complete Level 6
Complete Level 5
Complete Level 4
Complete Level 3
Drink two cups of coffee
Didn't fall down the stairs
Complete Level 2
Complete Level 1
Tip Tony
Completed Sams house only breathing in 15 times
Drove 150 km per hour
Spoke perfectly
Kill every robot
Complete Story Mode Co-Op
Get bronze or higher on every time trial
Get silver or higher on every time trial
Get gold on every time trial
Unlock all the Achievements in Manual Samuel
Skipped a cinematic
Went to work without shoes
Blow up Tony
Made no stains on yourself
Blink 2000 times
Found every hashtag