Meditation to help with ADHD and migraines

I just happened to stumble across info today that indicated that meditation is helpful in dealing with migraine (which I deal with) and also with ADHD in adults and kids. This study showed nearly an 80% improvement in symptoms  with meditation. How do you do it? How do you even start? There are lots of free apps to help, but here's some great info to know before you dive in, but just know that you don't have to spend a lot of time and there is no perfect way to do it. And if you have tips, please share!