When using any dating site, free or paid, there will be certain norms and expectations most members should consider. This includes how you portray yourself to other members first and foremost. You want to find the best match for you, so the last thing you want to do is misrepresent yourself or upset a potential love connection.
Be honest when describing yourself and use current pictures on the POF dating site. Using a picture of you from 10 years ago, or when you were in better shape won't do you any favors. The person who meets you may be extremely upset that you chose to lie about who you truly are.
Also, when contacting members whether it be through POF messaging or instant messaging, use class and etiquette. Don't approach members with sexual requests or weird questions like "what are you wearing right now?" Again, things like these will only create possible conflicts and may get you kicked off the sie.