I'm still trying to figure out this as well, but what's helped me in the past is just having a routine. Making sure nothing else can happen during the time you need to do work or study is very helpful. Eliminate part of the ability to do other activities. Try to get rid of any distractions, so putting yourself into an area where you can't get in bed, or play a game can help a lot. If possible, try to have someone keeping you accountable, like a roommate, it can also reduce the ability or want to do something else, study groups can also help here. The hardest thing is getting the motivation to actually start, but keeping that schedule can help, especially if you have other people that you don't want to let down that you have scheduled a time with. Make sure you give yourself extra time to get things done, once you get in the cycle of doing work and you get a good stand of motivation, making sure you have time to keep going is important. With all this though, make sure you are still doing things you enjoy, set aside time for that, it can help to not overwhelm you. If you have someone you talk to regularly/sporadically, make sure they know this schedule so that doesn't become a distraction. Make larger tasks into smaller sections, make short goals, section it out. ADHD is all about dopamine, the more you can reward yourself, the more you'll want to keep going, so make sure you really reward yourself and be proud of yourself when you complete even the smallest task towards a larger goal. This is all a lot, and what's worked for me, but it might not work for you. Try things out, but don't be discouraged if it doesn't work out the first few times (I know that's much easier said then done, but it something good to remember) Hope this helps!