To create a new ticket or send an e-mail to a client, press the "create a ticket" button. By default, user is specified in the client field, start entering the client's e-mail instead, in case the client is not yet in the database, use the + button and add a new one.
Then you can enter the subject of the ticket or e-mail, its content, attach files and set the SLA term. You can also specify the parameters related to the ticket.
There are 2 options to create a ticket:

• Ticket is created on behalf of the client, as if he applied to you and you create a ticket at his request. This option is used by default. In this case, the ticket will look as if the client has initiated correspondence. A notification message will be sent to client.
• The second option is to initiate correspondence by the agent. The ticket will be bound to the client, but in this case the agent initiates the correspondence (roughly speaking, writes the e-mail to the client). In order to use this option, uncheck the "From client" checkbox when creating a ticket. Also in this case another notification will be sent - the "Template of ticket creation".

Let's try to create a ticket form on behalf of Alexander Ivanov - as if he applied to us. We write the subject of the letter, the content. Press the send button. As we can see, the ticket was created as if Alexander Ivanov had addressed us.

Now let's try the second option. Let's create a ticket. Enter the contact, topic and content. Uncheck the "From the client" checkbox and create a ticket. 
As you can see, the ticket is bound to Alexander Ivanov, but the first e-mail or post was created from me.