To my knowledge I haven't committed any HUGE gaffes. Thank goodness. I probably butted into a few twitter conversations I shouldn't have when I was a newbie. Sometimes the people chatting really aren't asking you to add your two cents! Although no one ever said anything to me about it and please feel free to add yourself into any conversation I'm having on twitter. If I want to talk privately to someone, I'll go offline, no worries.
Is overuse of exclamation points a gaffe? I do it ALL the time...
When I started doing social media I tried to remember that the Internet is Forever, and not to say or post anything I wasn't going to live with for the rest of my life. Sometimes I'll write a really snarky tweet and then delete it character by character before sending it. Just not worth inviting the trolls or the flames.
I forget sometimes that just because I Follow someone, they aren't necessarily Following me. Someone with half a million Followers probably isn't going to be conversing with me a lot.
The one thing that annoys me, is when I Follow someone on twitter, and right away up pops a Direct Message asking me to friend them on Facebook, buy their book, review their book, sing their song (well no, actually I've never seen that request)...you get the idea. SO turns me off. I'm an author too, you know? And I didn't just spam you. You seemed interesting, maybe someone whose tweets I'd enjoy, and in time I might well have meandered over to the Zon and checked out your books...I don't unFollow just for that though. Unless I get more than one DM of that nature from you.
Ooh, and do NOT add me to your newsletter or subscribe me to your blog if you get my e mail address somehow. Not without my permission. There's one author who shall be nameless who did that and I cannot figure out how they got my address and I'm still livid. This person isn't even an author in any genre I read, they posted like daily, so I was being flooded with notices....sigh. I unsubscribed more than once. Saw a new message from them in my spam folder yesterday.
When all else fails (my new favorite video):