I said how to do it in BBCode to avoid activating HTML in a post which affects my default setup, so I usually post it in normal form then edit it just to activate HTML. In HTML it's pretty easy..
test:<p style="text-indent: 3em">eeeeee</p> Edit:... that's still HTML and not BBCode, as I can't use it unless I activate HTML code in this post. And be forced to use <br>, div, and etc.