1) learn
2) analyze
3) apply

if you haven't learned songs in the style you want to emulate, do it now. that covers 1).

if you don't know how to analyze the songs you want to emulate, you need to learn theory (among other things). if you don't know theory, learn it now. that covers 2).

if you are good with 1) and 2), write the music. do it now. that covers 3).
Anfangen ist leicht, Beharren eine Kunst.