well the name of the game is you want to be able to keep bait AT bait site and not allow a bear to come in grab some and carry off

when cutting hole in drum, be careful to not leave jagged edges, as no reason to injure the bears that eat out of it with sharp edges
I would watch some hunting videos to see designs of other baited stand sites, as for securing barrel, I would think wrapping some good sized chains around drum and chaining to tree strong enough to hold it would work!
as for what bait to use, , always remember a few things, 1 bears find things by smell
so foods with scent that lasts and is strong would be at top of my list,
but also keep in mind that after the season ALL bait has to be removed and that means even residue ion many states!
more liquid scents/baits , can mean having to dig dirt up to remove evidence of it at the end!

NEXT< bears are little kids IMO< they like JUNK food, sweets, fats, corn

guides I know, that used to bait always used things like bacon grease, fat, fish, donuts and candy's, even old cooking oils/ry oils!

but again, where they baited they could use and wasn't an issue for them after the season on removal as rules maybe different !

another thing many baiters due, is place logs over top of bait, this way bears have to DIG to get to it, and this allows time for them to judge bears(which is also why many use 55 gallon drums, they use the drum as a TOOL to measure the size of the bear in comparison to the drum, but when doing this, keep in mind father away from drum, larger bear will look to it, and NOT be as BIG as drum at all!, think how some folks take pic trues of fish or game they kill making game look larger than it really is, by holding out father from the person HAHA)

so, like stated, what you carry in will need to be carried out after season
this can get tricky and messy pending bait used!
but scent is top of list to me, then flavor of things, sweeter the better IMO, and smaller the pieces, the longer a bear has to stay at bait to eat it, big pieces they can grab and walk off with, as even bears know MOST bait sites are traps, some will be dumb for easy meals, but many will be smarter than you think about it
and again, females with cubs many times will show up and leave CUBS behind, (due to many times MALE bears are at sites and or just out of fear bait site is a trap) so, try and learn how to ID females, all the more so if there NOT allowed in your zone/unit/area!
no one wants to see a cub die due to shooting its Mom I gather(but it also happens and can be 100% legal too, its just something I suggest before pulling the trigger to look closer females due have things you can id MOST times, if you have time to look)