This guide on how to hack a WordPress theme is not for accomplished WordPress coders, nor is it for neophytes who don’t have a clue about XHTML and CSS.
This is what an experienced designer needs to be able to bend a solid ready-made WordPress theme to his/her will and make it his/her own. We are principally after the design her and not the code.
I will be adding sections to it as they occur to me. Feel free to send in suggestions for aspects you would like me to cover or helpful tricks you think would help others.