OK, with respect to restraints, I've tended to have a particular appreciation for simplicity. Rope is great and there are many rope practitioners that are outstanding but there is something to be said for unyielding chain.

Get yourselves a set (four) of leather cuffs with "D" rings. You can find them easily at most SM shops and the best are very soft leather but absolutely unbreakably strong. Then rig your bed.

Purchase some good link chain at your local hardware store. Feel the chain before you buy it and make sure it is smooth and doesn't have any sharp edges or points that may injure you or your partner. Also buy a number of quick link chain connectors, which look like links but have an end that will screw into a thread. You can also use screw pin shackles. Alternatively, you can use padlocks but they're kind of expensive just for securing the chain to a bed.

Depending on how your bed is configured, you can attach the chain to the legs of the bed frame, to the metal bed frame or to headboard-footboard. You have probably seen slaves secured to the posts of a four-poster bed, you know the wooden dowel type that are turned on a lathe. Four poster wooden construction, unless the posts are designed to be load bearing are dangerous connection points.

Use padlocks to secure the cuffs to the chain. You can get same-keyed padlocks from any hardware store. It's always very sexy for your Domme to wear the padlock key around her neck, so I'd invest in a nice long chain, either gold, silver or platinum for her to wear for the key. You want the chain to be long enough so that it can easily be used to unlock anything without her needing to take off the chain.

The two of you need to come up with a signal that is clear and easy to remember that signals that you're in distress. She can build up your tolerance for queening over time. One real good signal is to hold a helium balloon in one hand and to let go of the string when in distress. You'll also let go involuntarily if you lose consciousness.

You need to be risk-aware and she should not try anything extended with you restrained unless she has learned an been licensed to use CPR.

Now, I realize you have asked for a Domme to respond and I'm not a Domme. But the experience I have had ought to merit something.