Originally Posted by PowerPyx
The stores marked on your map (clothing, gun shop, barber shop...) will not work for this.
You need to rob a mini-mart. They can usually be found at gas stations. One is right across the street from Franklin's garage, behind the gas station. Go in, aim at the clerk and wait for a couple of seconds until he has given you the money. Doing this will add 1,2% to your total progress.
I'll add more info about this to the guide.
I was just about to say "this info is in the guide!" then I realised it was something I added after you ported the guide over