There are two types of exams one must pass in order to get a physics degree and both require very different learning strategies. In the following I will explain two techniques, one for written, one for oral exams, that helped me get amazing grades in every exam.
Written Exams
For written exams the most important thing is that you are able to solve exercises fast without making any mistakes. Therefore the best way to learn for a written exam is to solve as many exercises as you can. Most people are lazy and thus it rarely happens that someone invents completely new exercises for an exam. In addition, inventing new exercises is a big risks.
There can be many mistakes in them, they could be too hard or too simple. Therefore most exams consist of exercises from books or old exams that were already tested countless times. By solving as many exercises as you can the chances are high that you will see something familiar in the exam is very high. In fact, no one is really able to solve a completely new problem in a physics exam. Most exercises in exams are variations of problems that you already solved as a homework problem or that were discussed in a lecture.
I always start by studying old exams and the exercise sheets we get. This way I know what concepts and computational tricks are important to my lecturer. I never wrote an exam without solving the exercise sheets at least three times, because knowing how to solve a problem is not enough. You must be able to solve them fast without making mistakes.
Depending on how much time I have I solve, in addition, old exercise sheets that are similar to those we got.
Oral Exams
For oral exams I learn completely different.
I always start by reading the lecture notes for the class and reformulate everything in there into questions. I write these questions on index cards and the corresponding answers on the backside. If I don’t understand a concept in the lecture notes I add it to a list. For many oral exams written protocols, which document asked questions and answers by the examiner, exist. I write these on index cards, too.
This way I get a big stack of index cards which cover every possible question and a list of things that I do not understand. Next, I invest some time to understand things that are unclear. I read about them in books and ask specific questions at Physics.Stackexchange.
As soon as I understand something I write it down as a question plus answer on an index card. Then I return to my stack of index cards and start answering the questions I wrote onto them, by writing the answers on a sheet of paper.
 After each question I check my answer with the answer on the backside.

 If I answered the question correctly I put the corresponding index card on my “green stack”.
 If I answered wrongly or didn’t knew the answer, but understand the answer on the backside, I put it on my “red stack”.
 If I don’t understand the answer on the backside I put it on my “yellow stack”.

 After sorting the index cards this way I take the yellow stack and try to understand everything I still don’t understand. Every index card from the yellow stack is put on the red stack as soon as my problem with the answer on the backside is solved .
 Afterwards, I start a second round of answering the index cards on my red stack. Again, I sort them into green yellow and red.
 I repeat this procedure until all index cards are on the green stack.
 Finally, I answer all questions in the green stack once more. By using this technique I got a straight A in every oral exam I ever took.
By using this technique I got a straight A in every oral exam I ever took.