When you click on the comments at the bottom of the post, a window should open that looks like this:
Of course, it won't have my name, but it will have yours if you are a Google blogger, in which case, you will probably not need this tutorial. I'm assuming that people who have accounts with LiveJournal or WordPress or whatever will know what to do.
The easiest thing for anyone else to do is to click on Name/URL. Then you will get this window:
You just put your name, whatever you may want to call yourself. You don't have to put your whole name or your real name if that makes you uncomfortable. The person who calls herself Grumpy Ex Pat, for example, well, that's not her real name. You can leave the URL space blank unless you have a webpage you want to share.
If that doesn't work, let me know.