So basically, maintain a tree topology from mains to devices.
Code:
amp----power strip----keyboard
|
|
Mains-------power strip----power strip---more stuff
| |
| |--Only plug power strips into this power strip
|
blah blah-power strip----computer
|
bass amp
Now, I'm wondering, how is this affected when you have too much stuff wanting power for a single breaker to handle, or practical concerns require you to do so (i.e. bass amp on the stage, your sound board in the back of the room are on different circuits, but DI-ing the bass connects the ground of the sound board to the ground of the bass amp)