1) Pick my picture(s). Copy the breast (and other, if necessary) areas.

2) Paste the breasts onto the picture, in Photopaint, this forms a "layer" -- basically, a separate image "floating" over the first (which is the "background"). Now I can (if need be) enlarge this breast-image to the appropriate size.

Layers

3) Move the breasts to the right spot. I usually set the transparency of the layer to 50% so that I can see underneath it as I move it. This helps align them properly. Set it back to 100% (solid) when you're done.

Breast Selection	Transparancy at 75%