You’ll have to measure your own wagon since they come in so many sizes, but I use my own measurements in this example:
Step 4: Turn your cover right side out and iron all of the edges.
Step 5: Set your sewing machine to about a 6 or 7 stitch length and top stitch your cover 1″ from the edge ALL the way around. I draw this line with the disappearing ink pen as well. It just helps me keep all my lines REALLY straight.
Step 6: Measure the circumference of your wagon bed and multiply by 2/3. This is the length of 3mm elastic or elastic cord you will thread through the casing you just created.
Step 7: Sew the elastic ends together when you get it pulled all the way through.
Step 8: Then top stitch your opening closed!