Fills

[mangorockfish]

When you are chopping along and decide to play a short fill, is it taken from arpeggios or from parts of scales, or just melodic notes you chose?

[ShaneJ]

Yes, yes, and yes.

[250sc]

Yup, the only rules are make it sound good and don't step on what others are playing or singing.

[Jim Broyles]

You can also repeat part of the vocal melody as a fill.