I also use the elastic string purchased from the fabric store. It is cheap and works really well. When I wrap the string around the guide foot I wrap it around twice. It is easier to tie that way.

I have found that in order to properly keep pressure on the guide to the blank so the wrapping thread climbs up it properly and to keep the guides from turning each guide needs two elastic strings on them. That includes single foot guides as well.

Try the elastic sting method. Since each guide needs two strings or bands on each you might find it is easer for you to use a combination of elastic and tape. Sometimes I use a thin slice (around and eight of an inch) slice of tape as well.

Whatever works is the best method for you!