How to Sew Rouleau Straps

Rouleau straps were one of the techniques set for the contestants in the Great British Sewing Bee 2013.
The method shown in this video is taken from a book published by Singer in the 1920s. No special equipment is needed.
The strap is pulled the right way round with a piece of cord. Two ways doing this are shown. To give the strap extra strength, use the first method shown and leave the cord inside the finished strap: if a cotton cord is used, make sure that it has been washed first to prevent shrinkage.