Carefully reading the text is essential for that. You can't learn to speak French by merely sitting and listening, and you can't learn mathematics by watching someone else do problems. It's useful to work with other people on homework as long as you're involved as an active partner. See the syllabus section Homework Policy and Suggestions. But that's only the beginning.
Formulas are just tools.
Some routine problems, admittedly, are designed merely to be sure you really can handle the tools, but when attacking a non-routine problem, don't just try to hunt around for a formula. But some won't be. The purpose of the problems is to help you understand the ideas and techniques, not merely to learn how to do more similar problems. Stay on top . Sometimes it's hard to keep up with everything, but it's important not to fall behind in the course.