I have been a physical therapist for almost 10 years.
As a physical therapist student, I remember vividly sitting in neuroanatomy class while the professor was telling us, "You have to become an APTA member. You want to start as a student and keep your membership active throughout your career." She also said, "Go to APTA's Combined Sections Meeting every year!"
I'll admit, over the years it has become difficult to attend every single APTA CSM, given work schedules and family life, and I have let my APTA membership lapse a few times. But eventually I came back, and I'm glad I did. I've had so many professional experiences with APTA and its community that were truly unforgettable.