you can see guide at bottom of Spoiler: Mythical Wyvern.
yep. Slim Player & Female NPC Texture packs by Zilem. perfect design. i always play with 'slim player'
i dont known how her can work with 500 - 1000 files modify. this is huge process
1. go to wiki page and get ID, Project...
2. Use TConvert to convert xnb to png file and search with ID item
3. Open png with photographic softwares. and replace it with new design.
4. after complete design. export image and package all following construct of texture pack...