Random strum patterns
How I 'invent' strum patterns myself is like this (also nice for jamming):
Move your hand in sixteenth- or eighth-note-feeling over the strings (down, up, down, up, etc.)
and just randomly pull up your finger without stopping the movement.
For songs or playalongs I propose repeating the same pattern,
you will get a feeling for this... enjoy !
Aula de Benedict, 17 Set 2012