Rule #1

Never paint tired. Or drunk.

 

It may seem like fun at the time, but you'll end up making sloppy mistakes and wasting a lot of paint.

 

If you absolutely must do the art thing in either of these states then work on something not-important. A life sketch or thumbnail ideas for compositions, but never, ever, ever times infinity- work on an important project while tired.

 

Save it for when your brain is functioning at 100%.