There is no magical Tour that will work for everyone. Sorry.
What kind of traffic do you get mostly? What's your content?
The design itself has to accomplish one thing and one thing only: get them to the Join page/process ASAP. You want them to linger on the Tour....but not to LINGER on the Tour (or they will whack off instead of joining).
It's a tricky balance. A-B testing is your friend and so are reasonable expectations (a 1:1000 conversion ratio to start). Also, once a site 'reaches its level' don't waste time or resources chasing that extra 10-15%.
Best of luck.
