It's a tradition in our home to make are Halloween costumes. My son's design their own and also pick out the fabrics. It's a fun thing for us to do and it's a chance for me to share my love of sewing and design with them.
A lot of time goes into their costumes so mine kind of gets pushed to the side. I'm usually coming up with something last minute but also appropriate for my kids school Halloween parties and nothing that will "embarrass them" like that one time I showed up as a Scottish Bagpiper. I love this shirt because it's very Morticia esque but can be a base for any type of costume: witch, bat, vampire, hippy, flapper etc… I'm going to add some eye ball beads on the trim and spiders which my boys both agree will be "cool." Everything for them right.
Supplies are just a basic long sleeve shirt and another tshirt for the trim or a jersey type fabric. You can make this trim go as long as you'd like by cutting longer strips.
Tutorial go here
A couple other great bases for costumes you can find from my blog that most likely things you already have below…