When I was about age 10, my neighbor let me borrow an old
pair of long, skinny snowshoes so I could learn to navigate the
woods and fields of upstate New York in winter. The bindings he had
made were simple affairs of inner-tube rubber from truck tires. Over
the years I have used several different types of bindings on various
snowshoe designs, but for general use I have gone back to the rubber
bindings.
The photos show the bindings for a size 12 boot. Get a heavy
duty inner tube from a tractor trailer tire if possible; most
commercial tire shops have old ones for free. The outer shape of the
binding is not important, but the location and size of the boot slot
is. Start small and carve at the sides and heel until your boot just
scrapes through after some effort. The smallest knife cut or nick at
a corner will tear out with use, so I use heavy scissors or shears
once I have started the cut with a knife.

snowshoe front - click here
A 1/4 inch arch punch is ideal for putting 3 to 4 holes at
the two sides where the binding is lashed to the master cord of the
snowshoe with parachute cord. If you look closely at the photos you
can see the 3 inch rubber disks that go over the attachment point
and have the same hole pattern as the binding. They reinforce the
attachment point and reduce tearing of the holes.

snowshoe pattern - click here
Depending on the size and style of your boot, you may have to
experiment with how tight to make the toe strap part of the binding.
If it's too loose, your boot will be sliding forward too far into
the toe hole of the snowshoe. Having it too tight will put extra
strain on the holes at the attachment point, leading to a shorter
life for the rubber.
I especially like these bindings if I slog into overflow.
Unfastening a leather buckle or rope binding when it has become a
ball of ice is no fun, especially with frozen fingers. The rubber
bindings remain surprisingly pliable in the cold.
If you take a tumble in deep snow with these rubber bindings,
your boot will pop out of the toe hold (but the snowshoe will still
be attached around your boot). This is actually a safety release,
similar to bindings on modern skis, that gives way instead of your
poor ankle or knee.
Many years ago I read sound advice about snowshoe bindings
from Johnny Thorpe, a professional trapper from the Adirondack
Mountains of New York. He recommended unhooking your heels from
snowshoe bindings whenever crossing a river or working near a beaver
lodge, where ice could be rotten. The toe hold alone will keep the
snowshoes on your feet as long as you walk forward, yet the shoe
will pop off with a twist of your foot if you go through the ice.
Having ice picks (with loosely-fitting point covers) in your parka
pockets and a partner to help are also good ideas when crossing
questionable ice.
The only terrain where I have found the rubber bindings to be
too flexible is steep pitches on hard-packed snow. The Sherpa-style
snowshoes with foot cleats and solid bindings are much better in the
mountains, where overflow is often confined to narrow creeks and
usually avoidable.
Alaska Trapper, September 2003