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- [Costume Modding Tutorial] [An Easy Visual Guide] | Undertow. You will need Flash to publish SWF files.
If you are just starting out with modding then it may be prudent to begin with custom hair designs (using
GIMP or
Inkscape). You can get familiar with templates, importing and testing your work in-game, working with the layers which compose the SDT scene, three-tone shading, color-matching, etc... Hair files can be created using either vector or raster drawing techniques, but you'll need a basic grasp of vector graphics if you intend to work on clothing mods.
Once you're comfortable with that stuff, you can grab a trial license for Flash and tackle the additional challenges of ActionScript, advanced layering, multi-sprite clothing designs, breast slider accommodation, and so on.
If you find that you
don't enjoy the visual work then there are other avenues to explore, such as Loader modding and dialogue creation.
If you enjoy the visual work but
don't like the Flash stuff, then you can continue to just draw stuff. There are various modders on the forum who will happily publish your designs
(hey - it's an easy coauthor credit in exchange for a few minutes of work )