If you have ADHD, then focusing on an important task, such as studying, can be difficult. You're continually aware of everything in your surroundings, and temptations are very hard to overcome unless you deal with them at a time when they don't feel tempting.
When I went back to school as a 27 year old, I knew I had to think out strategies to cope with my ADHD, and they had to be very different from and much better than "just pull yourself together". Most of these strategies were based on behavioral science, so instead of trying to change myself I altered my environment so as to minimize disturbing input, possibilities for escape, and positive rewards for behaviour that ran counter to studying. I also started making a "study playlist", but instead of using calming, peaceful music, I based it on emo, pop-punk and lighter metalcore.
The idea is as follows: This is music with a lot of energy and a high tempo, and therefore it will act as an outlet for restlessness. At the same time, it is not very challenging to listen at. A lot of it is built around the same patterns as regular pop music. In spite of being very angry, it is pretty easy listening. And it's pretty similar, you skip from one track to the next without noticing. In short, it takes away restlessness without intruding on your mind!
This is still a work in progress, and will probably remain so for a while. If you have comments about flow ("this track would fit in better here") selection ("you have far too much strung out") and suggestions for additions, then I'm open for suggestions.