If you think that after you join the site you'll insantly start flirting with other members - get down to Earth, as you won't (just like you won't on bunch of other hookup sites). But if you really want to get laid with help of a casual dating site:
1. Make sure your profile is looking attractive and doesn't sound stupid
2. Don't post pictures of your 'best friend'. You'll introduce it to her later if you're lucky enough
3. Send messages to the members. If you think you sent enough... send more!
4. Ignore model looking ladies, check their pics with Google search
5. Have yourself membership on couple other hookup/casual sites (FlirtyDater.com, AFF, HookupHangout.com, etc. - you choose)
6. Repeat 1-4
Good luck!