Best Prison to do this on is Centre Perks 2.0.
Like it states you have to go 3 consecutive days without raising your Guard Heat above 0 in a single session. You can pause but you can’t quit out and go back in.
You do this by following the routine it asks you to do in the top right-hand corner and don't cause any trouble.
Start a new game in CP 2.0 and you can do what I did below if you having any problems:
07:00 – 08:00: Roll Call – Get to the Roll Call area ASAP and wait until next routine.
08:00 – 09:00: Breakfast - Just sit down in any chair in the Food Hall and wait.
09:00 – 12:00: Free Time – I just went back in my prison cell and laid in bed so I didn’t get into any trouble or see any guards.
12:00 – 13:00: Lunch - Like breakfast, just sit down in any chair and wait.
13:00 – 15:00: Job Time – Go to the job office and sit in the chair and wait.
15:00 – 16: 00: Exercise Time – Just use one of the equipment’s, I didn’t even press any buttons to do the exercise, just made sure I was on one.
16:00 – 17:00: Shower Time – Just follow everyone and go to the shower room and use one.
17:00 – 18:00: Dinner – As before, just sit down in any chair and wait.
18:00 – 22:00: Free Time – Like the last free time, go to your prison cell and wait it out.
22:00 – 23:00: Roll Call – Get to the area ASAP and wait until its time for bed.
23:00 – 07:00: Lights Out – Go back to your cell and sleep - Time flies by.
Do that 2 more times and achievement is yours when you get to Roll Call on Day 4.
Quick tip: When you load up your new game check your desk to make sure you haven’t got any illegal items in there and if you do hide them in the hidden compartment just in case you get picked for a cell search.
Guard Heat is the icon on the lower left where the hand/baton is shown, NOT the stars that appear if you miss a routine.