Starting a reboot and urgent questions

This is my first post to nofap so I'm pretty excited about getting started and getting the great results that comes with the challenge. I'm 24 years old and have been addicted to not only masturbation but anything that gives me a rush. I've never used drugs but I'm addicted to caffeine and any other kind of legal stimulant. I've noticed over the past couple of months that my erections haven't been like they used to be and my morning wood isn't hard like it should be. Needless to say it scared the crap out of me to think that my junk wouldn't work especially if I were to be with a chick and nothing happened. I've been with two chicks since I've heard about Porn Induced ED and the results weren't bad but could've been so much better. I have currently been hooking up with two different chicks and have only had sex with one so far(They are both gorgeous and we are close enough to have sex so you can see my predicament here). I'm nervous as hell to hook up with the other out of fear of not having the best erection I can and not leaving a good impression. With that being said I have some questions about the reboot.

1. What things should I avoid on a reboot? Books detailing sexual stuff? Risque pictures but still clothed? Rated R movies? (Please give me all the tips you can, I want to do this thing right!)
2.Can I have sex on a reboot and could it possibly help in rewiring the brain to human stimuli?
3.Do stimulants hurt your results?
4.Foods or supplements that help with blood flow for erections?
5.Is it always at least 90 days or do full results come quicker?

If there are important questions that I haven't asked please feel free to suggest some things that I haven't thought of. Thank you to all the fapstronauts out there and lets do this thing!