I got tired of finding the mixer bit and a drill motor every time I wanted to mix some paint, SO:
I picked an older drill motor and cut a piece of PVC pipe as a holster. Mounted the pipe to the end of a bench where I kept most of the paint. I use a peg board hook for a mixer, nothing fancy but it works and was quick. Plus it is cheap to replace.
My Father made one years ago. He was a master carver so he carved a propeller and mounted it to a shaft. To his surprise the propeller pumped all the paint out of the can and onto the ceiling in a second.
The peg board hook doesn't do this.
Step 1: Storage Holster
Here is the drill motor in the holster. Nothing fancy, the PVC pipe has a wood bottom so paint doesn't drip on the floor.
Step 2: Using Your Mixer
So not a hard project, but it sure is nice to always be ready to mix paint.
Good Luck, be careful and have fun.