This could go the same way as the high hat thread!
Whilst there aren't any set rules, there would still be an unwritten structure using bars...16, 32 64 beats etc...if you dj, when do you cue the record in? It would usually be on the first beat of a new bar...thus hopefully in sync with the bar structure that most dance formulas follow...but having said that, there will always be an exception to the rules...
Listen to some favourite tracks, get an idea of structure, use it by all means, but find your own style, rather than bringing the bass in on the 65th, just because matey has done!