I took the GRE for the first time recently and my Quantitative and Verbal Reasoning scores were somehow good. However, I've scored only 2.5 on the Analytical Writing section and I believe that would kill my application even to a small graduate program (I'm an international student applying to chemistry grad schools). Now I am studying to retake the GRE and I've found plenty of materials for quantitative and verbal reasoning, but I am struggling to find (free) content on the internet on how to prepare for the AW part of the exam. Are there any resources online or books that can help leveling my writing skills in the short term? (I'm planning to retake it by october)
I don't have any specific sites or resources but I have some advice,
Write, write, write, and write some more
Get a notebook and set aside 40 minutes every day to write a sample essay. A list of topics can be found on the ETS.org website (so I guess I have one resource :) ).
Then analyze and grade your own essay. Compare to the template, to any available sample essays you find, etc.
The best way to improve writing is to write.