I've posted to my Tapestry Share blog about one of the methods I've used quite successfully for many years for warping the Tissart tapestry loom I have. I've used this process, or some modification of it, for other upright tapestry looms. One of the weaving students at the university assisted with this post by going through the steps while I photographed her so that I could put images with the written instructions.
http://tapestryshare.blogspot.com/2014/04/tissart-tapestry-loom-warping-one-method.html
Tommye