1. Log into you Gmail account, select Settings and then Labs. Scroll down and select Canned Responses. Enable this feature and save settings.
2. Now return back to the Compose Mail section and you will see a new dropdown menu named Canned Response. Click on that, select ‘New canned response’ and enter a suitable name for it and then click Ok to save.
3. Next type what you want in the message field (your auto-reply message) and click Save button to save the message. This is your auto-reply message, which is now ready to send. It can be accessed from the Canned response dropdown menu. (you can create any number of canned response to send),
4. Just choose the canned response you just created from the dropdown list and the message will be pasted in the email body automatically. No need to type the whole message.
Now how to auto-reply to email messages? You can automatically reply to selected messages by creating a filter and selecting a canned response.
1. From your Gmail account select the create filter option. Then specify the criteria you'd like to use for determining what to do with a message as it arrives. Type “From email address”, specify any subject or specific some words in the email body and click ‘Next Step’.
2. From here, you can choose any action you want to perform. Select “Send canned response” and select the previously created canned response (auto-reply message) from the dropdown list and click Create Filter button.
3. Now whenever you receive an email message with the subject or words you mentioned, your canned response (your auto-reply message) will be automatically sent to the sender.
Hope this tutorial will be helpful to you.