noname2200 on 25 July 2008
The easiest way I know of involves having access to the toolbar, so again you'll have to be quoting, editing, or starting a thread.
Once you do so, type your comment in full, including whatever it is you want to spoilertag.
Highlight whatever word(s) you want to spoilertag. Now click on the button marked "Select Background Color", which is represented by a small pencil with the letters "ab" next to it.
A pallete of colors pops up. Select the black one: the others will not do as thorough a job.
The words you highlighted now appear to be black. To read them, simply highlight them. Be warned that smileys are not spoilertagged properly, for what it's worth.
