Sarcasticly sell the "post on steemit and get rich quick" narrative. Make a second anonymous account. Make all the mistakes new users make... Plagiarizing, worthless content, begging for attention and ultimately "it's not fair" rants and show new users how ineffective those are. Then post something of value and show it earning. Obviously make it humorous lol.
That or explain how steemit/steem/SP/SBD works through interpretive dance, sock puppets, etc.