Knots
Clove Hitch on a Bight
First Off
I'm no pro at this. Before you go tying somebody up make sure you've established some boundaries, have a safeword, all that good stuff. I highly recommend Jay Wiseman's Erotic Bondage Handbook. It probably has more info on the practice of bondage than on just knot tying, but hey, anybody can tie a knot, it takes a bit more know-how to tie a person.
Background and Observations
I found a knot that I think is better than other knots for tying a single human limb to a solid object such as a bed post. I say that I found not invented it because I'm sure someone else has tied it before, though I haven't seen it anywhere else to my knowledge. Time to dig out Ashley's again.
Let me tell you a bit about what I know of tying bondage and how it applies to this knot.
There is a saying "tie people up with the ropes, not the knots". What that means is basically this: use knots and wraps in the right places so that you can tie a person up without tight or complicated knots. One thing that this means is that bondage knots most often begin at the middle of the rope so that the ends can be tied safely out of reach of fingers, toes, and teeth.
Clove Hitch on a Bight begins at the middle of the rope (which it is a good idea to mark). This way the ends can run happily away to the bedpost (preferable to chair leg because falling down when you're tied up sucks) and be tied together out of reach.
The second major point about bondage that this knot addresses is that of pressure distribution. Though some people do enjoy a certain degree of pain (myself not excluded), you'll be more likely to get someone to let you tie them up more than once if you don't hurt them the first time.
I've read about and tried various wrapping techniques for single limb bondage, and one problem that keeps coming up is that as many times as a knot loops around, the pressure always seems to be concentrated on the first and last loops.
Clove Hitch on a Bight, according to those whom I have tied it on, does a better job of distributing its pressure equally between the 4 loops than other knots I have tried on the same people.
The third issue about tying people up is that there is an optimal tightness to which a loop around somebodies body part should be snugged. This tightness does not cause tingling or numbness, and a finger should be able to readily slip between rope and skin. Once snugged to this point a good knot shouldn't pull much tighter, even if they do tug and thrash about. My observations show that this knot is effective at both adjusting to the proper tightness and staying that way.
A final note about tying people up: use thicker rope. Twine or parachute cord is all well and good for decoration or camping, but has a little too much bite for most people's skin.
Tying Instructions: Clove Hitch
First you need to know how to tie a clove hitch. If you already do then skip down to the Clove Hitch on a Bight.
Clove Hitch: Step 1
Pass the rope back behind the "post" and then underneath in front.
Clove Hitch: Step 2
Above the first loop, pass the rope back behind again, and then underneath itself in front as before.
Clove Hitch: Step 3
Pull it snug and you're done. It is a very flat lying symmetric knot, much neater looking than my poor drawing.
Tying Instructions: Clove Hitch on a Bight
Now for the new one. It's almost exactly the same, the only trick is that you tie it with the middle of the rope rather than an end.
Clove Hitch on a Bight: Step 1
Folding the rope in half and treating it as a single thicker rope, pass it behind, and underneath in front, just like the first step of a traditional clove hitch.
Clove Hitch on a Bight: Step 2
Back around and underneath in front again. The trick here that takes some practice is to give yourself just barely enough rope to leave a small loop for the next step.
Clove Hitch on a Bight: Step 3
Now you've tied a clove hitch with the rope doubled. The innovation here is that you tuck the 2 tails through the loop, and settle the knot snug, leaving the ends separate from the knot.
Clove Hitch on a Bight: Step 4
Now just settle the knot into place. It takes some practice to give yourself the right amount of line to make that loop in the previous step. Make sure your rope is thick enough, thinner can do something like that square-knot collapse trick and slip tighter.
This last drawing isn't the best, I'll have to take a photo at some point, but now I'm out of time. Feel free to email me if you have any questions. Just remember, except for that last step of tucking the ends through the loop, the Clove Hitch on a Bight is tied exactly like a Clove Hitch, only with the rope doubled over.