Start with beats, learn how to make the common patterns, then get a synth and bung some notes in and flick through the presets, when you find 1 that sounds ok start fiddling with stuff while its playing so you can hear what everything does.
Leave samples for a little while, or use the 1s in the sound banks/refills til you get the knack of what does what to the sounds.
Oh yeah, read the tutorial/manual and stuff.