This isn’t required, but you can download the PDF version of the Airman Certification
Standards for Private Pilots.
https://www.faa.gov/training_testing/testing/acs/1512 You can read the
instructions on how to use the ACS. The ACS is essentially the study guide
for the practical exam. Any subject is fair game at this point. Have at it.
You’ll receive all of the required books upon selecting a start date, but
the FAA has the same books in PDF versions online. While you’re reading
through the ACS, you will notice a list of references under each topic.
They’re coded. Find the corresponding codes here:
That should keep you busy for a while. It should also keep you organized.
At least you know that you’re studying relevant material.
But like Chris said, the best thing you can do is get as many writtens done as you can.