Here's an exercise I find very useful to develop this:
- Play time (swing, groove or whatever you feel like) for 32 bars. Make a note in your head as each 8 bar section of the AABA structure passes. A = 8 Bars, A = 8 Bars, B = 8 bars, A = 8 bars.
- Now solo for the next 32 bars (still A,A,B,A) continuing to make a note of each 8 bar section.
- Then Repeat. Try and give each 32 bar solo a different colour or character.
This exercise is of course useful for jazz playing, where a drummer is regularly required to play to a strict structure, but it can also be extremely useful for other idioms. Adding these boundaries will give a new sense of melody and symmetry to your playing that can be otherwise absent in a free solo or shedding session.
Here's my attempt at this exercise from a few days ago (note the AABA markers at the top left of the video):