First, from what
MGMAT says, schools don't place the premium on the AWA score as they do the standard parts of GMAT. In fact, they said schools look at any score that is a 4.5 or higher as "good enough." They also said something along the lines of schools aren't really sure how to weight this section (is it really an indicator of apptitude) of the GMAT, hence why they don't place a premium on it.
That being said, it shouldn't be that tough to at least get a 5.0/6.0. I like yourself, never really studied for the AWA part of the exam (I took the GMAT 3 times, and got scores of 5.5, 5.0, and 5.5, respectively), but here are two things below which I would remember. The two things essentially give you a structure to lay out your argument. Anyone, please feel free to chime in on anything I've written; we all have our opinions.
1 - The Analysis of the argument: First, state that the argument does have some merits, though "the argument is based on several assumptions and/or lacks information/support to support them." Then cite a couple of points - one short paragraph for each.
"For example, if the author would give us more information or state x about his assumption, then it would help support the underlying argument, y ." Perhaps include why this is important/relevant, or what the implications are of not stating this.
2 - The Analysis of an issue: First, make sure to state something similar to, "The issue stated above is very complex, however, I believe x is correct approach for several reasons." Then proceed to use a short paragraph for each of your points.
One of the "Issue" prompts I received was something like.
a) Schools should teach practical skills in classes.
b) Schools should teach all sorts of subject matter.
Ultimately, there is no "right" or "wrong" answer for this question. That being said, you should feel free to use personal examples in your life to support your argument as why you believe one side.
Hope this helped.