ok i'm still learning about playing these too, so im glad you started this trhead, but going off my experience and what i've read in this forum...

if it's heads up, i reccomend NOT calling pre flop, unless you have a read that the OPP will fold if he misses the flop and/or turn and he's not a short stack. with a read, you can float which means you call (or raise) his c-bet when theres no A/K/Q, intending to bet enough to fold him if checked to on the turn (or keep him in if you hit the draw) since checking after a c-bet usually = over cards and they fold.

with no reads, if he always c-bets to give you bad odds, you don't know your fold-equity, and/or implied odds...it was a leak to call pre flop in the first place. But if you are pretty sure he actually has a hand AND stack that will pay you off if you hit your draw, like jackvance and yorib wrote, drawing against pot-odds is ok assuming you have implied. Or if you are pretty sure you can float, it's ok too. But with no reads, it's a bad play IMO.

also, if you're only playing a SC for value (not for fold-equity), keep in mind your odds of flopping 2 pair or better are around 40:1. that lets you think what size the pot needs to get to for a pre flop call to be worth it.