I wanted to use up some pearl cotton, so I made a couple basic threaded-in bands. The first one was the usual mess - Knot the warps at either end, shove all the tangles down and back towards the knots, and pray for the best.
I did better on the second! I took each card and used a lark's head knot to attach the 'far' end to a small dowel (actually a pencil). I suspended the pencil from my weaving hook. Then, card by card, I picked each one up and ran the card from the far end to the weaving end to untangle the strings. And then I tied it off on a chair-back, using a half-hitch and a slipknot. When they were all done, and the cards were properly set up to start, I undid all the slipknots, gathered up the weaving ends, and knotted them overhand. Then attached to belt and started to weave (after checking the card order again).
And it occurs to me that what I macguyvered out of a pencil and a chair looks an awful lot like the Oseberg tape loom (which is two uprights held up by a crossbeam). I always thought weaving "sideways" on the Oseberg loom would be awkward (although I've never tried it) but it sure would be useful for getting set up!