I'm thinking Spring too Skaduzy. The next one would be June so that's summer.
ScubaK it's really your choice what you'd like to make, I just kind of go with the season, but it is your theme choice. Never really thought about size but the ones I have sent or received have been like a picture frame size I guess, maybe 16 x 18 or 18 x 24, just something that would look nice hanging on the wall if you wanted or perhaps if you have no wall space you could use it as table mat. Hope this helps you a little.