1) At first click on the Settings button (Top Right of the page, Circular Symbol) and then click on "Settings".
2) Next click on "Accounts and Import".
4) Next, to add new Mail Account click on “Add a mail account”. A box will appear where Gmail will ask for your mail address. Put your mail address there.
5) Next, select “Import emails from my other account POP3" option and click the "Next >>" Button.
6) After this, you need to put your full email address, POP Server as “mail.YOUR-DOMAIN-NAME.com” and your Email Account’s password that we provided as “Password” and click on “Add Account”.
Thats it. Now you will be able to receive all mails inside your Gmail Account.
Now, Gmail will ask you that whether you want to Send Mail using the same Email Address (that you have added as POP3 just now) or not! To do this you have to follow the instructions below:
1) When Gmail asks that whether you want to send Mail using your Email Account (of your Domain) from Gmail, just click “Next >>” button.
2) Put your Full Name. And, remove the “Treat as an alias” tick sign, and click on “Next Step >>”
3) In the next step you have to write “mail.YOUR-DOMAIN-NAME.com” as SMTP Server, your Full Mail Address as “Username”, and your Email Account’s Password as “Password”. Select 465 as port. And, select “Secured connection using SSL”.
4) Now, click on “Add Account”.
5) Now Gmail will show a Form to put a Verification Code. And, the Verification Code will be sent to your Domain’s Mail Account, therefore at YOU@YOUR-DOMAIN-NAME.com. Check it and put it in the Form.
Thats it! Now you will be able to send mail using your Email Account from Gmail mailbox.