The thing that boosts my creativity is laying in bed at night with a drawing pad and crayons (yes, as in crayola!) and just letting things roll out.
I mostly use crayons because it reflects my art...basic, simple.
Kindergarden level in my mind.
Because of the crayons I can convince myself that I’m going back to a mental state where I didn't care what it looked like in the end. It all looked like great art to me. No room for criticism.
And the delicious smell of crayons; like the smell of lumber, or fresh cut grass (After the gases of the lawn mower blow away!).
And journaling about ideas...you start writing notes on one idea as you go along and then a bunch more ideas start bubbling up.