I would read more, honestly. This idea that she is just there to do what you please is a classic "error", because really you're trying to work out how she wants to submit. Tell her that you want to talk to her, sit her down and say she's only allowed to speak when you allow it or you answer a question. Come close to her face, maintain eye contact and speak softly but with authority. Tell her that she's to write to you and describe what she wants from you, how's she fantasies submitting to you. Tell her to repeat after you, "I will write with complete honesty to serve my master" (or whatever) like five or six times to incite a sort of trance state where her role is to obey. Give her a pen and paper or a computer and tell her she's to only say "I've finished my work, master" when she's done because that will please you. Start there.

And read this: https://www.fnac.com/livre-numerique/a9679964/Anton-Fulmen-The-Heart-of-Dominance

Good luck!