I do n ot use commersial lures or cover scents. I know of no one in my group of 15-20 season hunting buds who has ever attested to any of these making one iota of a diffeerence.
For 40+ years I have collected urine from deer that I kill. I pass it through a simple coffee filter. Freeze any excess. I use it to make a drag rag in hopes of partially covering my trail scent. I also use oiled-up tarsal glands off of bucks I have killed, rubbing these nearby where I set up in hopes of arousing the curiosity of a downwind buck. Not sure if either of these work all that well but think it has helped on a few occasions, especially the tarsal trick.