Mike, as soon as you type '@' sign, and start typing the name (as in AR username) you'd see the selection - of which you can pick up the member. Now this person should be a part of the communication for this post - or you should be following this person.

Here's example --- Mike Tizzano  - I just tagged you!

I learned from the answers here. Thanks.

I'm so glad you asked this question.  I was doing it the hard way.

Did you try it?

Mike Tizzano , you see? Just add @in front of any name. We used to get points for tags, but AR decided we have too much fun.

The answers here are very good, but you don't have to be subscribed to the person to tag them. 

Oh, I know so many people have answered this..but here goes.... Type the "@" symbol followed by the person's user name, usually one or two letters and it will pop up with some choices, hit the person you want to tag and continue on....

Great question Mike. I had forgotten how to to this myself.

I have been here for over 5 years and I don't know how...don't feel bad.  But then I am not a big computer geek.

Good question, Mike Tizzano and answers. I was wondering about the same thing! Thank you, Ron & Alexandra Seigel and Melanie Cameron! 

@ and their name. Don't worry, I had to actively search to figure this one out. I should have known it would follow Facebook's lead. Not sure why this isn't made more apparent.

Mike,

It is simple.  If you are subscribed to that indivual's blog, or if they commented on yours, go the"@" sign and a blank box will appear.  You start typing the person's name, and a drop down menu will show up.  Click on the name, and the tag appears.  Hope this helps, A

Praful's answer....

Looks like you and a few others learned from the answers, hope you are doing well Mike.

Because the topic being discussed may be of interest to that person.