What bike is it? Might be a model specific piece of advice someone can give you. For my CB360, I would NOT use Hondabond (at least, in lieu of a gasket) on the side covers. There's a certain amount of clearance provided by the gaskets, and given the way some bikes have oiling channels machined into the covers, you can mess with spinny bits if there's not enough clearance (e.g., I've shaved off tiny bits of the slinger cover by not providing enough clearance between it and the spout inside the clutch cover).
In general, for me, it'd be two steps - give the fixing bolts/screws on the case another quick snug - not overtight, but see if they'll turn a little tighter. If that doesn't fix it, you've got two options - survive it until you need another oil change and then make sure that your gasket surfaces are brilliantly clean (I use a fresh razor blade razor, but YMMV), and try a new gasket (option 2 is to skip the waiting for the oil change and just do it now, if you don't want to wait it out).
