Hello Julie
In order to insert smileys, you got to select "Post Reply", which will take you to another page where you will find the smileys on to your right hand side. Just click on them and the TEXT equivalent will appear on the text content area. For more smiley options do click on the [more] link at the bottom of the smiley section.

You can also preview your post by selecting the appropriate button at the bottom before posting.
Do ask us if you have any more questions
Have a good one!