The capes are fairly simple to make. It takes me about an hour to make one because I sew everything on. However, you don't even have to sew if you don't want to and it would be faster. Here's materials list if you plan to sew.
If you don't plan to sew then buy 30" of fleece, iron on velcro, and a sheet as a fusible felt (usually with the regular acrylic felt sheets in a craft store) or double sided fusible interfacing and felt.
I like to use fleece for two reasons. First, you don't have to sew the edges. Just cut it out in the shape you want and go. Second, after a child is done saving the world for the day they can curl up underneath their nice soft cape and rest. One 30" piece of fleece is enough for three 3 capes. The 30" width of your fleece is the length of the cape. how to make your cape: open up your fabric until it is a large rectangle (will probably be 30" x 60")and cut into 3 smaller rectangles are about 20" x 30". This will fit most children ages 2 to 8. If you need a larger cape just buy a wider cut or work your fabric vertically.
Using the simple pattern below cut "a," the neck hole, centered at one of the small edges. Using cut "b" go to the to shoulder edges of the cape and slice those out at the patterns angle. Cut out your Velcro to be roughly 1.5" x 1". Sew or iron it on the tabs formed when you cut the line to the neck hole.
To make the Superhero Letter I used "Pauls SUPER font" which is free on dafont.com. I typed a letter and free transformed it to fill the 8.5"x11" printing area and printed it on the no-wax side of freezer paper cut to that size. In case it might save you some trouble, here are all the letters I used. If you need a letter I don't have, make it with "Pauls SUPER font."
After printing it on the freezer paper iron it onto your felt and cut it out.
Pull the freezer paper off and sew or iron your letter on.
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