Hi altairahmad,
The AWA portion of the GMAT is remarkably standard - you essentially have to write that an argument is flawed, explain why it's flawed and offer some suggestions about how to make the argument stronger. As long as you stay 'on topic' and present your ideas in a structured way, then you should be fine. There are a number of different 'templates' that you might choose to use; DisciplinedPrep has linked to a popular one on the site (in his post, above). Beyond that, you should make sure to write the Essay every time you take a practice CAT/mock - so that you are properly ready to do so when you take the Official GMAT.
Integrated Reasoning involves a number of skills that you would learn when training for the Verbal and Quant sections. IR is remarkably similar to Verbal CR - you just end up having far more information to deal with in IR. Thus, proper 'active' reading, note-taking and sometimes some basic Math/DS skills are required.
Have you taken any practice CATs/mocks yet and included the IR sections? How have you been scoring so far?
GMAT assassins aren't born, they're made,
Rich