My fiancee has agreed to be my sex slave for my birthday, for the day only. We're both new to this situation though.
She has agreed that there will be some rules, but other than having her call me Master and that she must agree to anything I ask, I don't know what other rules there should be.
Advice please?
There will be spanking as punishment, but also for fun too
Yes, we have already discussed boundaries.
My birthday is not until July so we have time to organise our plans for the day.
It's a slippery slope to play at. Jus' sayin'.
Yes, we intend to have a safe word.
Before you can even begin to do something like this, you need to know her limits, the soft ones you can push and the hard ones you must never cross. As the others have said, a safe word is also a must. You as the Dom must also remember that her submission to you is a gift and not something that is offered for abuse. Treat her and her gift as she should be treated and your rewards will be unlimited in the pleasure she will bring you. I wish you both the best of luck in you endeavor.
If you are planning on have a gag of some sort, find another way to signal a "safe word". Options are listed in the 101 topic I think.