Speed jump as loads of people have said.
Low 1st jump to give you plenty of pump.

A start ramp might not be abd idea if you really need it, even just a bikes legnth would be a good boost.

Our trails, http://video.google.co.uk/videoplay?docid=4180721854492647105
Start ramp, rollers and small jumps to start. That should get you going. The video is a bit s**t but it was the first thing i ever made on wmm years ago so what do you expect. And just to point out, its not me in the vid as i was filming and i can only do the small stuff cos i'm a pussy

seriously nice trails dude!!!! thnx fro the tips guys!

Pedal or just build a big roll in. if you do flatten the ground or clar it then let it dry before riding it, in the wet it ruins the run with big tyre marks all over, plus slows you down in the dry overall.

 Towing is a good  idea but it can be dangerous + youve got to find someone to tow you every run