Accounts and Importstab.
Send mail as:field to the right of your email, there will be an
edit infobutton. Click this button.
Name:the field, write the desired name.
If you want to change the name in all Google services at once (including Gmail), the instructions below are for you:
Manage your Google Accountbutton.
Personal Infothe button.
NAMEfield in the profile settings.
Here we go! Now the new name will be used by default in all services of this Google Account (Gmail, Google Play, Youtube, etc.).