Start small/with what you know each step when working through a problem.
When you get stuck at a step, try to find the concept why.
Then attempt another problem, then another, etc.
Approach student manuals the same way as well. If you didn't get the answer right, no shame in checking how someone else did it. Without that last part, you're just copying and pasting while relying solely on trying to memorize a bunch of problems and their solutions, which isn't sufficient. However, understanding why each step was made means the lessons are internalized instead.
People hate on solutions manuals, but ones that work a problem out step-by-step are really helpful for the process, as long as each step is understood. I think it greatly helps understanding a problem when used with a textbook. In many ways, you could use a textbook to supplement a solutions manual.