The Spring 2021 semester starts soon (January 25 to be specific), so be sure you are registered for classes. There is still space available in many classes. Take a look at the schedule of math classes to find which classes have open seats. Then head to MySierra to register.
If you're looking for ways to study smarter, take a look at this article on Vox.com: Here are 8 tips for studying smarter.
Good luck this semester!
Your friendly Sierra College Mathematics Department