Start: Our new home (built in the 70's) had the brick painted white.
All white... but I wanted the natural look of original brick.
First, I painted the "grout" to a gray color before starting on the warm brown colors for the bricks.
By this time... I was already thinking, "what have I gotten into???!!!"
Starting to look kinda cool...
On and on and on... one brick at a time.
I used little plastic cups to mix paints. Latex, maybe some acrylic.
Done!