In order to add your group please click the box of dots in the upper right corner. Once you click that a menu option should appear. Scroll down a few clicks until you see contacts and it will take you to a new browser for contacts. When entering the new browser on your left hand region at the bottom you will see an labels option aside it is a plus sign to create a new label.

Now you are creating a new label which for example we will label "It Support". Once you have created your label you are then going to head over to the directory section on the contacts page. Once in directory search the person name at the top of the page you want to add. When you find the designated person you will see a arrow liked shape underneath their job description and local time. You will click that arrow like shape and it will state manage labels.

Under manage labels a box will pop up with the group name you created. You would click your group name and right underneath an apply button will appear. Apply the new changes to have this person added to your group and you will do that which each person you want in the group. After you have all the designated members in your group you will go back to gmail and compose a new email. Once you are in your new email type in your group label you've previously created and all the designated people will receive the email. That's how you create a group email!