i don't have a tutorial but i can try to explain... i used PS and an existing screenshot. this is the one i used: [link] avatarspirit.net is a really good source for them. pretty much fade out the screenshot and do the lineart of the characters over it with a 3 or 5pt brush as cleanly as possible. just do one smooth stroke for each line, try not to build it up with multiple strokes (doing a sketch layer might also help if you're not sure yet what you want the characters to look like.) you can trace over some of what's already there, like clothing, if you want to use it. for example with this one, jung's clothes are the same as the guy from the original screenshot, i just slimmed his waist and bulked up his arms. it helps a lot if your characters are similar in height/build to the ones in the screenshot. the poses should also be similar, just try to have them occupy around the same amount of space as the original characters. the coloring is just solid colors and cell shading. the shading in korra is very dark and the colors are muted, so it helped me to try picking up colors straight from the screenshot to use (for example, miksha's belt is the same color as the scarf of the guy in the original shot.) the background is straight from the screenshot. i used the cloning stamp tool to fill in spots where my characters were smaller than the originals (like around jung's waist.) this might take a little ingenuity to make it look consistent. finally, to get the same quality of lineart as the screenshot, i duplicated the lineart layer, used gaussian blur on one of them and lowered the opacity of both until it looked about right. just keep switching back between your drawing and the original until they look as similar as possible. tell me if anything is unclear and i can try to elaborate hopefully it makes some sense, lol.