Did you know that you really need very little in the way of supplies to paint outdoors? At first I didn't, in the beginning I dragged a veritable studio outside, two giant bags, an easel, and pounds and pounds of stuff! Then I got wise and looked at the endeavor as more of a simple sketching situation. This is one of the systems I use, a cigar box that I bought at a thrift shop. I squeeze paint directly into it ......and I've painted many paintings from it.
Painting: Celeste Bergin, Hillside, oil on 6x8canvas panel