The CBEST doesn't measure teaching skills. It measures proficiency in the basic educational areas of reading, writing and math, which is needed to instruct students in grades kindergarten through 12th grade. Passing or failing the test doesn't give any indication of actual teaching ability. If you have a bachelor's degree and prepare for the test, you should be able to pass it.
Everything you need to know about the CBEST Test can be found on the CBEST website. Take the practice tests there and see how you score. This will give you an indication of how much preparation you need and in what areas. Read about the test structure to know what to expect. Check with your local university to see whether there are any CBEST preparation seminars in your area.
Purchase a CBEST preparation guide or check one out from the library. Practice answering the questions and taking the tests. This will give you an idea when you're ready to take the test. When you feel confident, check out the test dates and locations on the CBEST website, register and pay your fee. Be sure to read the test rules and instructions on what and what not to bring with you on test day.
Being well-prepared for the CBEST should relieve anxiety on test day. Make sure you get a good night's sleep and eat well before the test. Know how to get to the test site and print out directions beforehand. Give yourself extra time to get ready and arrive. Bring a book to occupy yourself if you're early.
Find your unofficial CBEST score on the website about two weeks after your test date. You should receive your official score in the mail three to four weeks after your test. If you don't pass, don't worry. You can take the test as many times as you need. There are classes and seminars offered in most California areas and online to help you prepare.