Also, these will give you hoodless capes. If you need a hood, I think you'll need to sew and it will be a bit more complex. Would be easier in 2 pieces.
Yeah, so, we couldn't find a cape! Any suggestions on how to actually pull this off?
Easiest no-sew option is just to cut a piece of fabric in a trapezoid (narrower at top, wider at bottom), then safety pin at shoulders. You can get by without a hem for the short term with many fabrics.
If you're willing to sew, optionally hem and then fold down the top by say 1.5", then use your longest stitch to sew two parallel seams about 1/4" apart in the outer 1/2". You can then pull on one side of these to gather the cape until it's the right circumference for around the neck. Pull a wide ribbon through the new pocket and tie in front. Or, skip the ribbon part and safety pin to shoulders after gathering.
I'm on my phone and can't easily look up tutorials but there should be ome out there.
Thanks! I was worried about keeping it on him, but safety pinning it to the shoulders is a great idea!