What's the best material to use and method to secure them so they don't slide up & down the string?  Recently started using the EL string vs flemish as I haven't learned how to make a flemish but I'm having issues with the silencers sliding and the rubber strands coming out.

Here's the method I use.

 http://www.youtube.com/watch?v=gyGuPxe1BMA

I buy my material in bulk and cut the wiskers to 2" and put one top and bottom instead of two each though.

On my endless strings I use tie-on cat whiskers tied on very tight or string leeches.

I switched to yarn puffs on most bows unless I'm going to be hunting in areas with lots of "stick tight" type seed heads that will gum them up.

Sent ya an email,Kickapoo.
Mike

I tie a bit of dental floss above and below the silencer once I have it in place.

I just use beaver balls threaded through the strands and have never had a problem with them moving.

I've switched recently to the wool scallops that Two Tracks sells.  Last forever, can easily swap them from string to string, bow to bow, etc.  High value for a top notch product.  And dealing with the Deshler's is always a pleasure.  Of course, they're only going to work if you twist that endless string a bit.

i use terry's hush puppies (  www.bowhush.com  ) on all my bowstrings, which are all endless (of course    )  

hush puppies are new zealand wool and Super Tough, never had to replace any, and do a great job of silencing string vibrations.  they're simply tied on to the bowstring.