Login to the webmail portal, if you are unsure how to do this click the link below.
you should be presented with the screen below:
Click on the box at the top right that says “New” a drop down menu will appear, select “Email Message” this will bring up the compose new email window.
Select the alias you wish to send the email from, type in your recipients (multiple recipients can be separated with a comma), enter in any contacts you wish to Cc (carbon copy) and any contacts you wish to Bcc (blank carbon copy).
Enter your subject line, then the main body of the email, once you are happy click send.
You should then receive a pop up box in the bottom left of the window confirming that the email has been sent.