You're taking the ASTB so I'm assuming you're wanting to go SNA and/or NFO as first or second pick?
If you haven't already, go find some private pilot certification review videos on YouTube, they should be an hour long or more and go over a ton of aviation info and sections that will prep or supplement your aviation knowledge.
It's my opinion that a lot of the math and language sections are kind of set in stone for you now being a week out, so focus on your weak sections exclusively in the last week with minor review in everything else here and there.
It's an adaptive test so it will be slightly different for everyone.