What is the best way to get my SAT score up in one month?

Test Preparation
1

I took the ACT twice without studying and got a 26 C and 10 W, but barely finished each section as the time restraints were very difficult for me.

I decided to try the SAT in August to see if I did any better and got this without studying:
C: 1220
RW: 590
M: 630

However on my PSAT in 11th grade I got:
C: 1150
RW: 640
M:510

And in my PSAT in 10th grade I got:
C: 1190
RW: 630
M: 560

The 75th percentile for my dream reach school is:
C: 1490
RW: 740
M: 750

Obviously it’d be ideal for me to shoot for the 75th percentile, but I would be happy with getting above a 1400.

I am signed up for the Khan Academy SAT Program and bought the Princeton Review SAT book. I do not have access to any type of online course or tutoring. I picked the Princeton Review book kind of at random because I’d spent some time researching which was the best, and for every book there was mixed reviews, so I went ahead with that one because it was what my local bookstore had. I did not choose the Official College Board book because it was to my understanding that all of those practice tests could be found online/through Khan Academy.

I don’t plan on apply early to this school, only my safeties, because I’d like to apply once my first quarter senior year grades are on my transcript to show a stronger upward trend and this school only has early decision which I can not do because finances are going to be a huge deciding factor for me. Therefore I have 2-3 more times to take it, however it would be nice to get it as high as possible by October so I can better solidify my chances at my safety schools and not have to worry about it when working on applications for my target and reaches.

Basically I was wondering:

  1. How much can the average person starting at about my score get theirs up in a month?
  2. How many hours will I need to dedicate to studying everyday?
  3. How should I best use my resources to study?
  4. What other free resources are there/is it worth investing in any other books?
  5. If you've used the Princeton Review book or Khan Academy, were they helpful?
  6. Any other tips?

Also, if I apply early to schools and get in with a scholarship, but then get a higher score on the SAT AFTER I’ve been accepted, can I submit this new score if it would impact my scholarship amount?

Thanks.