1. Act Like an NPC
When invading another player in Watch Dogs 2, it’s important not to make it obvious to them that you’re there. On their screen, you appear wearing your current clothes and with the face of whatever online avatar they have set.
With that in mind, it’d be in your favor to wear more muted colors that blend in better with civilians. The same goes for your vehicle; a sportscar with an elaborate DedSec-themed paint job sticks out like a sore thumb. When you’ve got those down, get used to not driving like a maniac when you’re around the target. Drive close behind other NPC’s and don’t give yourself away by crashing into street lamps.
When you’re following on foot, walk. NPC’s don’t jog or sprint. If you do all this, your target will be far less likely to see you coming.