How do you make an adjustable bag strap?

How do you attach a slider to a strap?

The Slider is first attached to your strap. Thread the strap through the Slider, then turn under the end and stitch in place through all layers. Sewing through Straps can be bulky. Since sewing machines do not like to sew uphill, I use a Jean-a-ma-jig to start off my stitching.

THIS IS FUN:  Question: How do you do a double seed stitch?