Before scent lock, I always kept my clothes in a bag containing pine tags or fresh cedar (depended on where I was hunting). Those were the best cover scents I ever used.
Occasionally I used vanilla to good affect as an attractant/cover. But if other people were using it nearby and not being careful it became a warning rather than an attractant.
Scent-a-way and the other scent killers help, scentless shampoo helps, and scent-lok suits help. But I think that Crazy Farmer is right, the think that helps most is not being smelled in the first place.