it's quite easy ^^
1. pick an image you want to use as a tat.
2. get the CMFF clothing template from somewhere on these forums or the Secondlife.com hompage (not too sure where I found it anymore... O.o)
3. place the graph where you want the tat to be on the body in a new layer, with the aid of the template
4. make sure all other layers are invisable: now use magic wand to make a selection of only the black (or other colour) of your tat
4. in the channels tab of your layer box thingy, choose create new layer: this will make an alpha channel.
5. use the selection to make the area you will want to see white, while leaving everything *outside* of your tat black (black in alpha channel = invisable)
6. using a layer under your tat, making it one solid colour, to check with the other channels visable if there's nothing still solid outside of the lines of your tat, as this will cause a 'line'of grey around your tat which will look kinda ugly... adjust your alpha channel if needed.
7. save the whole as a .tga file with 32 bits/pixel (to include the alpha channel in the image). Make absolutely sure no other layers but your tat graph are visable, I made that mistake of making a t-shirt that showed the grid fom the clothing templates
8. you should be done now ^^ Any problems arise, I'll be happy to help you out further.
be sure to get the CMFF templates! the other ones available are useful, but not as nicely detailed and with handy guides as these ones are... (thanks LOTS to the person who made those ^^)
