Keep a tube of lock tight or superglue in your tackle bag. Get hold of the sea lice/crab and wipe its back until dry. Squirt some glue on and then stick your hook onto its back. Keep the hook upright and proud. Make sure you allow the glue to dry and do not stick your fingers together
This will keep your sea lice alive and scurrying all over the sand because it can't dig itself into the sand. This is Because of the hook on its back and that will definitely attract the fish if they around. Remember the glue holds very well and there's no need for cotton so it's as natural as can be.