There are many things that can bring people to Steem, but one of the most common things that people say is

"do you use Reddit or 4chan or some other social website? Do you like it? Who earns money from your use?"

The answer is usually "the company that owns it".

There, you can say that there is a place where if you participate, you get money, and it's just a social network with many facets, including clones to Youtube (DTube - DLive for videos), Twitch (DLive for streams), Instagram (Steepshot for pictures), etc., which allow you to share your things, comment, and earn money from every vote you get and many other things.

There is also the approach of "it's a strong market that will rise but it's in its low point so you should buy". People love pre-bull markets.

You can also invite people to do whatever they do (write, record things, take pictures) but post them on Steem for a few extra cents of income and in order to promote an open-source community that is trying to make the world more profitable for the people, without middlemen handling the money that is made out of every interaction.