Carefully study the text and the Study Guide until you understand the concepts and can do the illustrative and practice problems. Always do the practice problems immediately after the appropriate section of text. Work the practice problems on your own and then check to see if you did the steps correctly. After completion of step 1, work the homework problems. You should be able to complete most of them by using the appropriate formula, and without repeatedly referring back to the text.
Many homework answers are in the back of the text.
Check your homework answers after you have completed one, or several problems. However, do not use the answers in the back as a regular means of determining how to actually do homework problems. If you find yourself looking up answers and then trying problems several different ways until you finally get the correct answer, this should indicate to you that your understanding of the material is insufficient. Remember, on exams, answers are not provided. Often a brief e-mail interaction or a short phone call with the instructor can prevent hours of frustration.