As far as creating the actual texture image, the history/rubber stamp brush is your friend. Use it to place patterns around the edges of your map where the seams are, patterns which will blend together seemlessly when they meet. For a square map this should be a relatively easy thing. For odd shaped maps (like human figures), it's a bit tougher. As far as scaling, I believe the map gets shrunk, or stretched to fit the geometry. So it will depend on the size of the object you're going to apply your map to. The best answer is to start with the largest possible image size for your texture map and then shrink it to fit your model through trial and error test renders. Hope this helps, Unzipped