I learned from being a sub. I learned from doing. That's not to say that I don't have tricks up my own sleeves.
When i was very much younger my Domme at the time would have me sit around thinking of ways she could hurt me. Oh a belt or a dowel rod? not creative enough, not pretty enough, not stylish enough. So i would spend my day a lone in my room braiding thin strips of electrical wire for whips. I would design methods of being tied up. I read anything I could get my hands on which ended up mostly as De Sade.
When I was younger it was all pain and my tastes have changed a lot, thank god for the internet!
The internet has really expanded my kink. I don't sit around and thinking of how awesome it would be to force lactate a sub and wonder how that would be done... oh no I know how it would be done. Now I think of how to make it even more uncomfortable for her.