Yesterday I gave everyone permission to sketch poorly in service of their characters and games. (If anyone gives guff in regard to your efforts, send 'em to me!) The other side of that coin is – as the audience – to be kind to those doing sketches. Sure, if a sketch looks (ahem) sketchy, there's often an inclination to make a joke about it. I encourage anyone who is so inclined to tamp down that impulse. (And I say this as a natural smart aleck, for whom sarcasm is my primary language . . .)
As a player or GM, being in a roleplaying game can be an experience that's surprisingly intimate (for lack of a better word). You're trying to come up with little stories on the spot to convey unusual ideas for characters who are possibly little like yourself, and may even be radically different in outlook, age, gender, etc. A lot of times, you're putting your heart out there. That takes a fair amount of trust . . . which can be scuffed or broken by ill-considered quips from other players.
So if someone tries to make the game better by doing a quick sketch to get a point across, accept it in the spirit it's offered, even if the picture itself is less than ideal. Focus on what that sketch is showing you about the character or situation. Find something nice to say about it. (I note that some groups are just fine with good-natured ribbing, but realize that even "funny" comments among friends can sometimes hit a toxic point. Genuine expressions of appreciation and admiration amid jokes go a long way toward keeping kindness central to the gaming relationship.)
But above all, keep having fun! When it comes to good gaming, even a bad draw can mean a good win.
-- Steven Marsh