If you failed an exam and you are given a second chance what strategies should you use to prepare so as to pass with a good grade?

The answer to this is going to depend somewhat on you and
what sorts of things do and don't work for you in particular.  If you studied in a
particular way for the first test and didn't pass, then obviously you shouldn't study in
that way again.

The most important thing for you to do is
to review all the material you have that is relevant to the test.  When you review the
material, you should do as much as you can to interact with it.  For example, you should
not simply read over the notes.  That does not really force you to think about the
material.  Instead, make yourself flash cards about important facts and study the
cards.  Then, particularly if you have written answers (as opposed to multiple choice or
one-word answers), you should try to do things like writing little essays about the
connections between the facts on those cards.

For the parts
of the test that cover things that you read in a textbook, you might try to write little
summaries of the various sections of the text.  Go back and read each section and try to
sum it up in a sentence or two.  Then summarize the whole
chapter.

All of these things will force you to really
interact with the material and to think about it rather than simply looking at it
passively.  Hopefully, that will help you do well on the next test and on future tests. 
Good luck!