These servers should be set as MX records:
aspmx.l.google.com / priority 1
alt1.aspmx.l.google.com / priority 5
alt2.aspmx.l.google.com / priority 5
alt3.aspmx.l.google.com / priority 10
alt4.aspmx.l.google.com / priority 10
These are the server settings for the email programme:
Gmail SMTP
server address: smtp.gmail.com
name: your full name
username: your full Gmail address (e.g. you@gmail.com)
password: The password you use to log in to Gmail
port (TLS): 587
port (SSL): 465
SSL required: Yes
TLS required: Yes
Require authentication / Use authentication: Yes
Require secure connection / Use secure connection: Yes