You want her unaware...

"I want you to be unable to anticipate what I´m going to do to you." You say with a evil grin.
"But Sir, couldn´t you just have used a blindfold for that?" Kiera responds, sounding slightly confused.
"Yes, but then I would have to take those straps into account and I wasn´t gonna remove it at all anyway so I thought it´d be better if your basic hood blinded you."
"Oh." Kiera understands now. "So, what´s next, Sir?" She sounds eager but anxious.

You fold her arms up behind her back and place them in a special one-sleeve that you´d made. It **** the wearer to maintain a constant reverse prayer position which would get quite hard over-time. As you lace it in place Kiera complains that its to much, she can´t stretch that much. But you don´t relent and keep lacing it.

Finally, her arms are completely useless. Now for her mouth. You´d purchased a harness which you could then attatch a ball to to gag her with. Put you´ve also got a nice pump gag. And you´ve got your dick...