Lashings

Two things to remember about lashings:
1) neatness counts - a neat lashing is a strong one, and
2) first you wrap, then you frap.

Square lashings are used to join two poles that are at right angles.

Place two poles on the ground in the shape of a cross. Tie a clove hitch around the bottom pole near the crosspiece, then twist the free end of the rope around its upper part and tuck it out of the way.
Make three or four wraps around the poles, keeping the rope very tight. As you form the wraps, lay the rope on the outside of each previous turn around the crosspiece, and on the inside of each previous turn around the bottom pole.
Then frap three times around the wraps to tighten the lashing as much as possible.
Finish the lashing with a clove hitch on the opposite pole and opposite side from the first clove hitch.

Diagonal lashings are used to join two poles that are not at right angles.

Start by tying a timber hitch around both poles and pulling it snug.
Make four tight wraps around the spars, laying each wrap neatly alongside the timber hitch.
Make four more tight wraps across the first three.
Frap it three or four times and finish the lashing with a clove hitch.

Shear lashings are used two join two poles together lengthwise.

Lay two poles side by side.
Tie a clove hitch around one pole.
Make four loose wraps around the poles and frap three times between them.
Finish the lashing with a clove hitch on the opposite pole and opposite side from the first clove hitch.

A Tripod lashing is like a sheer lashing, but is used to join three poles into a tripod.

Tie a clove hitch around one of the outside poles.
Loosely wrap the poles five or six times, then frap between each of the poles.
Finish the lashing with a clove hitch on the opposite pole and opposite side from the first clove hitch.

There is a time and place for everything, and lashings are not the useful camp skill they once were, but they are still a valuable skill to know. Consider lashings these days to be basically a survival skill that you can practice when car camping, and you bring with you the poles you need for the project. You should never cut branches or fell trees on a backpacking trip to obtain poles for lashing together tables, chairs, tripods, and such. Building a Monkey Bridge or a signal tower is perhaps the best way to hone those lashing skills, but remember to respect the environment when building these projects.