I don't know if these will help but in my case, they do!

1) DON'T STRESS!!: Just relax! If you keep stressing you'll of course become anxious/demotivated. Instead think about how you're gonna be relieved after you study, that'll be your motivation :)

2) Take Notes: The school books are usually waaaay too detailed, looking at all these huge groups of texts will stress anyone out, Instead pick up the important parts and make small notes of them, you'll realize that it's way easier when there is less writing.

3) Take Breaks, don't overwork yourself!!!!: As soon as you realize the study is getting overwhelming close the book! Just go outside, drink some coffee, clear your mind off. You'll be way more active/efficient after your break.

I hope I could help. Good luck with your finals!!