Practicing and maintaining submissive postures and positions are a great place to start.

Make her write a journal for you. Things she does and how they make her feel. It'll give you greater insight into her needs, and what you do that's right and what you do that doesn't quite cut it...

I always enjoy a nice shower. Just stand there and let her do all the washing. If you have a plastic chair, bring it in and get your hair washed too.

Dictate her clothing options. Make her do out-of-the-house chores in risque clothing.

Go shopping with her... take a pass through the kitchenware/laundry/bathroom sections, ask her about any number of items, spatulas, wooden spoons, wire wisks, clothespins, etc. and ask her if she'd like you to buy "it" for (fill in the blank, whether spankings, insertions, etc.)

Get a massage.

Role Play:

Give a massage, but "abuse" her like the horny, blackmailing masseuer you are.

Play doctor like you always wanted to as a horny teenager.

Kidnap her.