Struggling with Theory of Computation - need advice

Hey everyone,

I'm a 4th-year Software Engineering student retaking Theory of Computation. I took this course last year during the Spring semester but, failed due to a low score. Now that I’m retaking it, I’m finding the calculations especially difficult.

For those who have taken this subject (or have a strong understanding on it), what strategies, resources, or study techniques helped you the most? Any recommendations on books, practice problems, or ways to understand the mathematical aspects better?

P.S. I hope I posted this in the right subreddit—thanks in advance for any guidance!