I think the best way to be a strong candidate is to keep your grades up and GET INVOLVED in any way you can. Meaning, volunteer in different settings (beyond the required 40 hours) and also get involved in the community in some way, get a job as a PT Aide or even in a fitness setting, coach a kids team, etc. One of my interviewers asked me what kind of community service I've done, and I had to say basically none, which he did not seem very happy about. Putting in real time in the field, or a related field will show a true interest in PT. This seems more valuable than worrying about honors and awards.
My GPA was poor, as I am an older student and got my degree over 10 years ago. Things are different now. I have 156 credit hours of post-bacc coursework (mostly art and real estate, and my remaining pre-requisites) and I carry a 4.0 now in those 156 hours. I hope they take that into consideration. As embarrassing as it is, here are my stats. They might not be great, but they got me an interview at SMU!
University: University of California, Santa Barbara '99
Major: Biology
Overall GPA: 3.16
Pre-Req GPA: 2.98 (and climbing...)
GRE: V160 Q158 AW 4.0
Volunteer: 70 hours @ post-acute rehab / skilled nursing facility
Good luck!