What outline should I follow in order to write a good augmentative essay (Arguing a Position)?

There are different ways to structure an essay like this. 
Different teachers might prefer different structures and so you might want to consult
with your own teacher.  I prefer the following structure to an essay.  (Of course, there
needs to be an introduction and conclusion, but I will discuss the body of the essay
here.)

In the body of the essay, you should argue both for
and against your major points.  This shows that you have understood that other points of
view are possible and it gives you a chance to rebut those other points of view.  There
are two possible ways to do this.

You could outline your
essay like this:

A.  Points against my
argument

B.  Points for my
argument

In each of these headings, you would give all of
the points against and for your point.  (I recommend doing it in this order so that your
argument is the "last word.")

Alternatively (and I think
this is better), you could go point by point.  In this format, each paragraph would
present the opposing point of view followed by your own point of view.  I believe this
is more effective because it puts the two arguments together in one place and makes it
easier for the reader to compare the two.

So, I would
structure the body of the essay into paragraphs where each paragraph gives a point that
disagrees with your point and then presents evidence to rebut the opposing point of
view.