Helmet strap continually loosening - suggestions on keeping it to size?
 

It seems that the strap on my helmet continually loosens up. I'd prefer it if it could stay at the size i need more or less permanently. Any suggestions on accomplishing this?

sounds like you have the strap incorrectly threaded through the buckle/clip.

Some helmets have little rubber bands on the straps that you are supposed to push tight up against the buckle to keep the straps in place. if you don't push that rubber band into the buckle after adjusting it, the straps will gradually loosen.

Also the upper adjusting piece that brings the two straps together might be loose, so check that too.

Find a small rubber band and wrap it tightly around the strap inside of the adjuster buckle. Make sure it's kinda tight because it's supposed to "choke" the strap down and keep it from moving.
Ernest

Guessing that you have the strap properly threaded... and it still slips. I use a small nylon zip-tie. Just make sure the locking part is away from your face and zip the strap end tight. It won't move again until you clip it off. (I've done this with two helmets)