Bait and lure choices are a matter of personal preferences. There is no one best. Put your bait right down the hole. Some trappers put their lure there too, others on the back lip of the hole. Only time and experience will show you which way works best for you.
any commercial fox lure should work. As Oldmink pointed out put your bait down the hole and lure on the back lip of the hole. I like to add a ball of grass or sheep wool down the hole on top of the bait to make the critter work a little harder to remove the bait. It makes the critter take a few extra steps in the trap bed trying to get the grass or wool out, giving more chances of him hitting the pan.
I have an opinion.(I know what they say about opinions )I don't believe there is any difference between baits and lures except the way they look.Here's why.You put both either down the dirt hole,under a rock,or in a pocket set.The animal has to smell both to become interested enough to stay around the set or decide to dig for what ever is in the hole.The animal doesn't know what they are digging for except it smells good or interesting.With any animal after they find the bait they are gone if they haven't been caught .The only time I mess with bait is with a dogproof.About the only advantage I can see with bait over lure is that you use a bigger gob of bait so there is more volume there for the odor to come off of.I figure why carry around a quart of bait when an ounce of lure will get you the same results.Would you bait guys tell me what you think about what I said?