Your sentence: I must look at my English grammar handbook again and do some revision after the long time of sleeping :),
should read I must look at my English grammar handbook again and make some revisions (or "write some revisions" or "revise my text") after my long sleep. (I assume you mean after your lack of using English for weeks? If so, then OK, BUT if you mean, "I need to sleep a long time (now)" then "after the long time of sleeping" would be "after I get a lot of sleep".
