Welcome to Xnations johnreck
Best way to convert TGP traffic? Well first off it depends on what you're promoting. If you're promoting a standard paysite I'd recommend filtering the traffic by first sending it to an FPA with 1 primary option and a few secondary options, all within the same niche of course. If you're sending to a reality style site I'd recommend sending the traffic straight there by advertising on your gallery all the free movie clips.
As for the galleries themselves.. keep the thumbs big 'n sharp, try not to use banners, rather use big bold bright text and text links. Keep your templates simple and build/submit a new gallery at least 5 days a week. After a week or two you'll notice the overall traffic to your sponsor will build and you should start to see some sales trickle in.