The easiest way would be to go to their profile and clicking the Challenge icon. If they are in your friend list, you could use that section in the Daily Custom Challenge section.
I just took a look and Daily doesn't have an option to add a name of a player, so the above two ways will work. You can also challenge from the profile card that can be found by hovering over their username in places like the the forum.
Actually, the Play a Friend button allows you to type in any name. Sorry for the misinformation 
Thank you, Martin. I followed your suggestion to use the challenge icon. I think that worked. That v3. way is even easier than before because I don't need to correctly type in the opponent's name. This is a game for the Team Iowa ladder challenge. I had not noticed the challenge icon before you mentioned it.
Well, when you start typing in the player name in the other option it will try to find a matching name, so that is also good too 
Starting with "Daily Chess" what are the steps to issue a challenge to a specific player? I tried creating a new game but couldn't find a place to put in the name of the player I am trying to challenge. When using v2 I knew how to do that. In v3 I don't. This is not a complaint about v3. I want to know how to do that in v3, step by step. The player I want to challenge is not a "recent opponent" and is not on my "friend" list. Starting with "Daily Chess" what are the needed steps? Thanks.