Free woodworking plans to build broad looms and weaving looms in various sizes. The quantity and quality of the instructions provided at these woodbuilding links varies.
A triangle loom consists of a triangular frame with a 90 degree angle at the bottom and 45 degree angles at the two upper corners. The frame can be made out of any wood that is smooth enough so that it does not snag the yarn. Nails are pounded into the face of the frame close the inside edge. These nails are usually 1/2 inch apart on the top rail and approximately 1/4 inch apart down each of the sides. The wood should be predrilled for the nails to prevent splitting.
Make a triangular African childrens loom by using the three dowels. Push the dowels into the ground (or wooden base) forming a triangle, two at a distance of 8 inches for the back of the loom and one centered between these two 12 inches away...
... weaving appeals to you, you may be glad to know that you can dispel your awe and discover the basic principles of the skill by building a very primitive device in your backyard.
Before weaving a rug, you will need a frame loom. Learn about rug weaving and how to weave with a frame loom in this free video.
A slow loading site for its pictures but if you are into making rag rugs from scrap material this loom may be what you need to assist in making rag rugs.
Here, we will reinvent basic loom mechanics from scratch -- step by step. Then, with my manual, Woven Structures, at hand, you can try whatever basic techniques you wish.