SSAT prep by yourself?

Do you think I’ll be able to prep myself for the SSAT all by myself to take the test in December? How much time would I need to devote? Everyday? twice a week?

Thanks!

I would first take a timed practice test, correct it, see if your score is around the range of schools you want to get into, and figure out what sections you need to improve in and do problems aimed towards those sections. The time you need to devote would depend on how much you want to improve your initial practice test score.
I would say that preparing a little each day would put you in good shape for the test, but this would again depend on what you want to improve in and how much.
Even with a practice score above those of the schools you want to get into, I would still advise preparing a little.