Smilies in my post?

How do I get a smiley into a post?

I finally figured out how to see the smilies choices. Sometimes I'm so slow! But when I tap on a smiley, a duplicate appears on the smilies drop-screen next to the original. I thought maybe it would be a drag-&-drop sort of thing, but no. The smilies are enabled. Is there a trick I'm missing? Thanks for any help.