I'm not real good at tutorials, but here is trying.
Just know that the slider button has to be as wide as the background. If there is transparency needed around the button, magic pink will be necessary, else it'll show up white.
I usually place the button on the background, (if it is round) then crop it out, so thet the blank sections of the round part are filled with the background, giving the appearance of transparency, without having to deal with magic pink....hate the stuff...ugh.
Anyway, if you need further help, maybe a voice messenger or phone call would be best.
http://screencast.com/t/nxcrYSNnx