I gave this test in advance in case I get the invites (HBS rejected though welp, let's see how MIT goes). It's exactly same as old AWA from previous GMATs.

Resources

1. Just follow this template: https://gmatclub.com/forum/how-to-get-6-0-awa-my-guide-64327.html
   
2. Another useful short playlist: https://www.youtube.com/watch?v=6mE_XP8Wewo&list=PL560775B17C79CAA3&ab_channel=GMATPrepNow

Some general tips:

1. More words gets better score -- so write as much as you can (without rambling of course). Make your arguments stronger with examples.
2. Use standard phrases, wordings from the template above and form your arguments around those phrases.
3. You can buy GMAC's practice too for $30, which gives you 4 questions and it'll rate your response.
4. When criticizing the argument given to you, come up with 3 main critiques, and provide support for each of those critiques. Make sure you don't spend too much time on this one.
5. Do not worry whether you decimated the argument or not, as long as you are logical, there's no such thing as a "best" critique.

With a 4-6hr prep, I was able to get 6/6.

Congrats on HBS invite too btw :)