I couldn't go too long without costume content, could I? So I looked through my pictures to see what I could post about, and thought bows would be a good enough start!
I used this style bow both on my 1869 day dress, and the green plaid 1850s ball gown. They're really quite simple.
Start by cutting two strips of fabric that will make the size bow you want. It's a little trial and error.
Fold the fabric in half down the center. Much like double fold bias tape, only there's no need to fold the raw edges under--these will be covered with the center of the bow.
Fold the edges down and run a gathering stitch along the bottom edge.
Pull the gathering until it's nice and tight.
Repeat for the second side and baste the two sides together.
Wrap a piece of fabric or ribbon around the center and sew it closed in back. And voila! A bow!