play games from HDD on xbox- help pls

hi guys
I want to soft mod an xbox but idk what I need 1st, guides say "Do this but make sure done this" and now idk how is 1st.
I want to play games from HDD, im thinking of putting a 500gb hdd and it will be sata so I know ill need a sata to IDE adapter.
So what I need to do 1st? have a modified dashboard? how is done? then what I need to do to the HDD? connect to xbox and put what program on it or connect to pc and then do what?
Is there a guide that I can read that have all the steps from the start?
Sorry for all the Qs but i been reading for a few hrs now and dont find a good guide.