This is a very nice project from one of my favourite magazines, ReadyMade. Here’s the instructions from their site:
TAPESTRY FOR TOES
Piece together a custom hallway runner. First choose a pattern—the more geometric and less curvy your design, the easier your cutting job will be. For our quilt-inspired rug, we used a utility knife to slice 8” carpet samples in half on the diagonal, making uniform triangles. Once your components are cut, lay them out, in order, on the floor. Attach each piece to its neighbor by applying a strip of that great fix-all—duct tape—to the underside of each seam.
I wonder if that would work for a big carpet, and instead of using duct tape maybe using carpet glue…We need a carpet to cover the crusty old wooden floor in the living room, don’t want to buy an expensive new one or a ugly cheap one. So making one sounds good.