When registering a new user in MyChat WEB version, switch to the tab "Registration":

 

webreg3

 

Then, enter login information, password, and email address. If you set a common security password for access restriction, specify it too.

 

If you check the box "Remember me on this computer", your browser will remember your account data for connection and won't ask you to fill it next time when you update the page in a browser using "Ctrl+F5" or open it again.

 

After that, To connect, press "Enter" on the keyboard, or "OK" by using a mouse.