I don't allow myself breaks even I want to drop everything. But of course I draw much slower if I'll not in the mood.
Here are my tips:
1) Deadlines every day
Not too crazy, because if I can't meet them physically I will just make things worse. But I have a monthly planner, where I write "September, 9th - sketch and lines, September 10th - colours and shading, etc". And it a great pleasure to mark things done.
2) Make a planner
This is connected with the previous tip, but it's a bit different things. For example I love how bullet journals look like and always get inspired and motivated when I find them. Even though they never worked for me. But trying different systems was fun. Now I have a Todoist tracker plus moodboard which I love to decorate. And they motivate me a lot.
From everywhere. My personal favourite sources are Pinterest and real life. Just watch and take pleasure.
No need to enroll to some expensive hard courses. Just watch some simple free courses that you enjoy. Few minuites a day and you get knowledge. And that makes you feel succeed and motivated
5) Music and sounds
These are really important for me. If you listening to hard or depressive music this might influence you a lot. Try some different moods. You may also try this site, it's not about music but about sound https://mynoise.net/
And also remember that you can do everything you want, just believe in yourself)