As stated by others, apply early!! PTCAS can be tricky and things are more likely to get delayed than not. Establish a rapport with professors and PTs you have shadowed in order to get the best LORs you can. Ask people who can truly speak to your abilities rather than a random professor you had 2 years ago. Write a killer essay! Emphasize what makes you unique, rather than vague and cliched statements. If you haven't already, get involved in the community, not just PT shadowing. Adcoms want to see a well-rounded individual, not someone who merely does what they are "supposed" to do in order to get into PT school.
It's a grueling process, but stay positive! If you are fortunate enough to get to the interview stage, make sure your passion and dedication to the field is apparent. Everyone gets nervous, but at the end of the day, you are there to make yourself stand out. Be sure to research each school so that you can ask thoughtful questions about their program. After all, you are looking for a "best fit" just as much as they are.
Good luck!!