Here's a very nice, simple way to make beautiful round braided challahs. It comes out much nicer than a simple 'snail' shape as so many do, and really takes only minutes to put together. Anyone who can braid three strands can make this challah easily. Plus it rises and bakes nicer than a simpler knot or twist does. You can also watch Jamie's video of the same technique.
Begin by taking three long strands and braiding them into a very long havdalah–candle-shaped log.
After this long 'candle' has been braided, carefully tie it up as if you are making one large knot out of it, and leave it to rise.
It will come out different than a simple round knot, and although not quite as extravagant as the woven round challah, it is still quite pretty.
To find out why we make round challahs this time of year read Rabbi Lawrence's Ask the Rabbi here.