As a newbie to the steampunk genre I had to learn how to do a lot on my own for budget reasons. I found the following tutorials helped a lot with making parts of my costume and my daughter’s.
DIY Belt (Ribbon/No Sew)
Tutorial list for Steampunk and Cosplay:
There is always Youtube for great videos and as always there are some great Groups on Facebook.
Sewing for Steampunk: https://www.facebook.com/groups/sewingforsteampunk/
-helped me out a great deal with some projects that I had questions on and couldn’t find the answers for.