I would suggest arranging the track so the drums are fully laid out. Intro, break, drop, break, outro depending on the genre. Get the drums layed out and hopefully you have a bit of a groove seeing as you are saying you can manage to get an intro. Keep adding to it and I promise you more ideas will come. If you have a bass line try throwing that melody in as your lead saw and build it into chords for your drop. That is sort of the reverse way of doing it (sort of). But that may help. PM me if you like.
-Graeme