If you happen to have such a bed in your house or a hotel, you might want to try this method.
I was wearing the following:
This is the bed I was talking about. The bed posts should be approximately at your crotch level. The decorative element which will be used as a plug (usually) can be replaced with anything more suitable. Check your local DIY shop.
Put a condom on the bedpost and be generous with lubricant.
Check the height of the "created" butt-plug
If it's too high put on high heels.
Bind your ankles and knees.
Use your imagination on what to do with the rope and what timer to use.
Insert the tip of the butt-plug.
And then sit on it with all your weight
Bind and cinch your hands using the chosen method. Now you can't walk off the post. All you can do is slightly move up and down and wait for the timer to release you.
In this example I used latex straightjacket.