Hi kamakshir

Of course u can mark answer on your booklet. Actually u will only get the question booklet in which u have to do all ur calculation and you will not get any extra sheets for rough work. But u should avoid doing any kind of the rough work on the OMR provided nor at the back or front. U should also not tear the question paper apart because it may cause problems.
Mark the answers in the OMR properly and also fill the details in OMR properly.

Best of luck!!