Complete a past exam paper under strict timed conditions without any notes or textbooks.  
Try to write an answer for every question.

Have a short break.

Evaluate your answers with the mark scheme - be strict and do not give yourself the benefit of the doubt on anything.  As you do this make a list of all concepts or topics that you did not perform well on.
The focus here is not to grade yourself but to identify topics that you need to brush up on.

Have a short break.

Systematically work through the topics on your list:
(depending on the length of your list you may need to do this in stages with breaks in between)

1. Read through the textbook for those topics.

2. If you have a revision guide, read through the topics in that also.

3. Refer to your own notes for the topics.

4. Make/use flash cards.

Read through and learn glossary definitions relevant to the topics on your list.

Check that your understanding of the listed topics has improved:

1. Complete homework assessments and other quizzes (e.g. Moodle quizzes) - these focus on basic understanding.

2. Answer some questions from worksheets.  Use extension questions where they are available - these focus on deeper and wider understanding.

Retest yourself with another past exam paper and check how you did with the mark scheme.