On a larger floor or table loom, you will have a reed and beater that will beat the weft into place. With Tapestry looms, the weft is usually beaten with a hand held beater. For this small cardboard box loom you can use a fork.
After each row of weft or pick, use the tines of the fork to beat or gently press the weft into place evenly across the loom.
Cardboard Box Loom
How to weave tapestry on a child’s Spears weaving loom.
Double Hole Rigid Heddle
Add beads to your weaving project.
Loom Weaving Books
The Weaver’s Idea Book: Creative Cloth on a Rigid Heddle Loom
Techniques include leno, Brooks bouquet, soumak, and embroidery on fabric.
UK: Weavers Idea Book