A tutor might be able to help you with revising. My suggestion to you is this however...
Do you do your homework with your notes by your side? Or do you do it by looking at examples? Before you do your hwk, review all your notes, review examples, etc... and THEN start your hwk. See how much of if you can do without notes at your side. This will be MUCH better preparation for tests.
Also... if you have trouble remembering, then you just have to study more. Don't ONLY study when a test is coming up. If you can make it a general habit to review things for lik 5-10 minutes each day, then chances are, by the time there's a test, you'll recall most of everything. Of course, this will take a good deal of work ethic... which not everyone has (I am one of them).
Either way, try different things to test your performance without anything next to you. Give yourself "quizzes" at home where you just flip to a random problem and you have to do it without checking anything else over.
It's worth considering... I don't know about the tutor... it really depends on whether it's all just a matter of memorizing, or if you THINK you know the material but instead you have just memorized steps instead of understanding it. But that always depends on the subject.