1) For every hour of precalculus class you need 2 hours of study time. For example, you have precalculus for 1 hour on mondays, wednesdays and fridays. After mondays class and before wednesdays class you should invest 2 hours of study time alone or in a group, Similarly for the whole week, don't let the work pile up, you don't want to wait till sunday trying to get 6 hours of precalculus studying done.
2) Use the resources offered by your school. Many schools have math centers or tutoring centers. School libraries often have study groups.
3) Talk to your classmates about forming or joining a study group.
4) Attempt every problem assigned using the textbook as a reference. If you get stuck, collect your work and show someone... a tutor... your professor... another student... anyone you think might be able to help.
5) Post your questions here, showing your attempt so that we may be able to identify your trouble and help you quickly.
Of course it goes without saying that class attendance is of paramount importance and you must buy the textbook (If you haven't done so already) Try to tweak the attitude 'my professor sucks' it may be true but that attitude only gives you an excuse to fail.