smell isn't an issue at all. when they're colonizing, they'll be so well sealed you won't smell anything. a lot of people use an incubator made out of two plastic bins, one inside the other, some water between the two and an aquarium heater.
your job is to get them from the sterilizer to the incubator with as little air or other surfaces touching them possible. you can add a drop of disinfectant to the incubators water if you want it really clean. plastic food bags off a roll aren't sterile, but they are very clean inside, which makes them good lids to cover the jars during incubation. you should cover them and not look for weeks or a month, every time you open and mess around, you risk contamination. try to forget them. water will condense on the lid of your incubator and rain down on the jars, so a sheet of tinfoil over them all to act as a mini roof is good
when you open a fully colonized fresh jar, it has a very distinctive smell. it's not strong, it smells kind of like really fresh soil and kind of nice in a way.
once you know it, you'll also know when a jar has gone bad, because it'll make you want to vomit once you get all the verm off. but you might also be able to smell a kind of sweet, acrid smell with your nose at the top of the jar while it's covered. bad jars aren't an issue smell wise until you take the lid off and then they smell like bad food. you can get rid of the smell, but try to avoid it by opening bad jars inside a bin bag, tying it up and taking it outside soon. breathing over contaminated jars is also a good way to get yourself a bad infection (they've been incubating close to body temperature = pathogens).