Ive been studying everyday since last monday. I usually study 2 subjects a day. For example, English from 1pm-4pm and math from 9pm to 12am. The last hour or so is usually a practice test but im running out of them. Has anyone increased their score that much in such little time? Im taking the ACT on September 17th. My gpa isnt good so my last chance at looking good for colleges is a high act score. 
I am in a similar situation as you are because I am trying to raise my score 4+ points in a very short period of time also and take the ACT in September. The biggest thing is building up the stamina to make it through a 3 hour test and not loose focus. But before you begin to take full, timed tests I would strengthen up any content weaknesses and obvious problems. Can I see your sections scores to see what you need to work on more?
honestly, probably not, you might get able to get 4 pts up max, but don’t stop trying.
I suggest you read the tens of other threads that ask this question (raising scores by a ‘good’ amount). There are many tips on them you could just read from there instead of making your own thread.
I’ll say what I and some others have said to the other threads to answer your questions (tips that worked for me):
-Master one subject at a time.
-Know why you’re missing it.
-How you can avoid missing it.
-Full-length practice tests for pacing
-Beat yourself over the ones you miss lol
Has anyone done it? Of course; in particular, my friend raised his by 9 pts with a tutor, I raised mine by 5 with what I just said above. Both of these were achieved between the Dec and Feb tests. Really sacrificed some time with friends and during school breaks but it turned out great. With the summer and the timeframe you have, just keep doing what you feel most comfortable with the material and you should be fine. I’m trying to build off a 33 this fall. Wish you the best of luck.
I’ve taken the ACT 3 times and went from 28 to 30 to 32. 6 points will be very difficult yet 4 is very achievable through hard work!
I jumped 4 points, it’s not impossible. Just make sure you’re reviewing your practice tests and recognizing your mistakes/weaknesses.
As others have said, I think 6 points may be pushing yourself too hard. Try for 4 points for now, and if you make that, then maybe try for the 2 more. Or you could always give yourself more time by testing in October.