Start by puting on the pair of shoes you want to adorn with elastics. Wrap a piece of thick elastic around the upper part of your foot (halfway onto your arch). The band needs to go all the way around the pump and overlap about a 1/2" on the underside, in front of the heel. Make sure it's tight so it won't slip down (just not too tight since we don't want to crush our foot bones!).

Cut elastic to correct length.

Sew on a sewing machine - just reinforcing the overlap area on the elastic. I've found they work best when the elastic overlaps at an angle - NOT one side meeting the other side exactly - to accommodate the curve of your foot. Repeat for other elastic.

See? The meeting of the two ends is at an angle - NOT straight on. Only really necessary for 1.5" wide elastic like this; for the thinner types of elastic it doesn't really matter.

Presto! It's like you have a whole new pair of shoes!

And I also tried adding thinner elastic to the ends of silver vinyl belting for a different look...

and sparkly silver ribbon for yet a third look. Both have thinner pieces of elastic sewn onto the ends of the contrasting ribbons. (The elastic is only about 1.5" long in-between, for the underlay part and to allow the band to slide over the widest part of the shoe at the toe.)You could do virtually anything! Chain overlaid onto stain...frilly ribbon with grosgrain in the center...a line of sequins...anything at all!

Happy DIY'ing!
xoxox
Carly