Stay friendly, polite, respectful and sportsmanlike. Ensure that your chat isn't interpreted as distracting, taunting or gloating and I think you'll be fine. If you don't have time to chat, then ignore it. If you find it distracting, disable it and if it's a recurring problem for you then disable it for all matches.
Chatting while playing

I guess I wasn't clear. The problem here is that I don't know how to do it. I don't want to be anything but friendly, social, and sportsmanlike, but I don't know how to initiate chat during a game. I don't see anything to click on.
You may be muted already or maybe the opponent has disabled chat.
I was inspired by how the pros occasionally use smilies (think the kids call them emojis these days) in Quake after particular moments (started by Cooller I believe) to allow myself to use smilies in chat. I figure also if you are playing chess in real life you can have an expression, right? Just no verbal. So now I very occasionally use the odd smiley in chat while playing after something major has taken place but anything verbal is shady if you ask me.

Just type something in the chat box or choose an emoji. It will initiate chat. I think the opponent needs to accept it though.
I sometimes make a couple comments, like when I make a blunder or when they miss a major opportunity. It keeps things human.
When the game starts, there is the board and then a big screen on the right of the board. All the way on the bottom of the big screen you will see a small box which says chat. Simply type your comment and hit enter. I also like to comment when I see something exceptional by my opponent, or simply on those rare occasions, hey this is really a great game, very enjoyable playing with you. I have had no issues.

When the game starts, there is the board and then a big screen on the right of the board. All the way on the bottom of the big screen you will see a small box which says chat. Simply type your comment and hit enter. I also like to comment when I see something exceptional by my opponent, or simply on those rare occasions, hey this is really a great game, very enjoyable playing with you. I have had no issues.
Yes, that's exactly what I'm talking about. A couple times I just wanted to say "oops". Or "I didn't see THAT coming". But mostly, it would be compliments to the opponent.
Pleased as I am finding a decent site to play on, online is severely lacking in comparison to playing live where you can see your opponent. A few comments here and there helps. I see that you are fairly new here so I will mention that some people have chat turned off. I personally miss comments at times because I am intent on the game. Don't get upset about it. Also many people leave immediately after a game is over. So what I have done when I am playing someone whom I am really enjoying playing and would like to play with some more I make a statement along the lines ........ Hey I am really enjoying playing with you, if you have the time and would care to stick around, I would be pleased to play a few more with you no matter who wins this game. I don't ask often and it rare that I decline a rematch request (which shows up by the chat box) but I do not see them soon enough sometimes to respond. Have fun, perhaps we will meet across the board one day.

When the game starts, there is the board and then a big screen on the right of the board. All the way on the bottom of the big screen you will see a small box which says chat. Simply type your comment and hit enter. I also like to comment when I see something exceptional by my opponent, or simply on those rare occasions, hey this is really a great game, very enjoyable playing with you. I have had no issues.
Are you talking about the box that says "message" or is there one that actually says "chat"? That's been part of my confusion. I've sent a number of messages, but have not gotten responses, so I thought there must be something I'm missing.

I sometimes just type something when I blunder or notice something I should have done a turn earlier. If I get a response great. If not its no biggie.

I don't take you or your explanations seriously.....man.

I have been muted for no reason.
No reason? That's just hard to imagine.....when reasons are so plentiful.

I accepted one of these chats. The clown accused me of cheating. His rating was well below mine and he blundered a couple of times.

I accepted one of these chats. The clown accused me of cheating. His rating was well below mine and he blundered a couple of times.
I'm sure there will be those experiences, but in my small number of chats, the opponent has really been friendly, respectful, and fun. It's been very positive.
I hope someday to be good enough to be accused of cheating.

Surprisingly out of thousands of games, I've only had a couple people get nasty and abusive over the chat. I'm also surprised there are not any scammers here. Try playing Scrabble Go app sometime...all the supposedly beautiful women start chatting and then try to get you to send them gift cards. I did get one of them to confess that he was actually a dude from Nigeria. Place is riddled with scammers.
HI Mikewrite,
Sorry I was referring to message which is what I thought you meant. (Message/Chat?) Played around a little and figured out > Click on the persons name. Click on more. Click on chat. That should do it for you. I have just use the message myself and works fine for me. As others have mentioned sometimes people just don't respond or they have chat turned off.
I've had a few opponents initiate chat while we're playing. I realized that I don't know how to do that, so how do you ask the other player for permission to chat? One game I was well ahead and when we started chatting, I lost my concentration and blundered...and lost. But it was a very pleasant chat otherwise. I really enjoy interacting with folks from other countries. Sometimes they just want to make a brief comment and not really have a conversation, and sometimes they just want to send an emoji. It's all fun, so I'd like to be able to do that too.
read replies to mike from me

I just had a guy tell me "You're so lucky I'm not in a mood for winning"..... just before resigning. Not exactly "abusive".... but really poor sportsmanship. I blocked him. He's from another country and probably doesn't speak good English, so maybe he didn't mean it the way it came across. Maybe he meant, "You played a great game and I'd love a rematch some time". On the other hand, maybe he meant "Everyone in your country is a pig". I couldn't see the body language, so who knows?
I've had a few opponents initiate chat while we're playing. I realized that I don't know how to do that, so how do you ask the other player for permission to chat? One game I was well ahead and when we started chatting, I lost my concentration and blundered...and lost. But it was a very pleasant chat otherwise. I really enjoy interacting with folks from other countries. Sometimes they just want to make a brief comment and not really have a conversation, and sometimes they just want to send an emoji. It's all fun, so I'd like to be able to do that too.