try hacking away at existing, simply organized themes, none of the fancier 'complete-looking' themes. it's actually kind of hard to gauge complexity by screenshot alone, so i don't know any target themes... themes these days are largely bar themes or floating boxed themes (modules hooked and loaded inside of lsbox, a module that allows for that); i recommend trying a bar theme first.

once you get the hang of configuring modules and understand how to tie them together, you'll figure how to 'theme' eventually.

also read as much documentation as you can. google 'lsdocs litestep' and try to understand the format of step.rc and how evars and bangs work.

it's normal to quit the process of learning and then resume some other month out of frustration/boredom/desperation/etc.