Becoming a Wordpress Theme Designer

[SeantheBlogonaut]

Just searching for a bit of advice on becoming a wordpress theme designer in the general sense. I am shortly to be unemployed and am looking at picking up some extra money through helping people devlop their own websites, at first using commercial themes designed here at Studio press but eventually when I have the skills perhpas designing my own.

I run my own blog and have set up a couple of sites for friends, I enjoy it but the paraniod anxiety freak in me wants the comfort of having some extra learning under my belt if I am going to charge people for a service.

So after that long winded explanation my question really is, where do I start? What do I need to learn to be able to trouble shoot first and then design at a later stage.

I don't know html (bits and peices for links etc) or any programming language (indicates how good wordpress is as a platform I think), whenever something doesn't work I bumble throught the forums here and usually find an answer.

So I was hoping for some recommendations, books, courses etc

Thanks in advance