1. Download and install PuTTY

2. Get the ID of the instance from Amazon EC2 console

3. Get the public DNS name of the instance from Amazon EC2 console

 
Select your instance and copy the value specified next to “Public DNS”.
 

4. Enable inbound SSH traffic from your IP address to your instance.

 
From Amazon EC2 console, select “Security Group”.
Highlight the security group your instance is associated with.
Click on “Inbound” tab and then “EDIT”.
Select Type “SSH”, and under Source select “My IP”.
Save.
 

5. Locate the private key and convert it from .pem to .ppk using PuTTYgen

For instruction on how to do that refer to How to convert private key of format .pem to PuTTY .ppk.
 

6. Start PuTTY and in the Category pane, select “Session” and complete these fields:

 
In the Host Name box, enter user_name@public_dns_name. To find out the appropriate user name refer to Amazon instance user names.
Under Connection type, select SSH.
Ensure that Port is set to 22.
 

7. In the Category pane, expand “Connection”, expand “SSH”, and then select “Auth” and complete these fields:

 
Click “Browse” and select the .ppk file that you generated for your key pair and click “Open”.
Click “Open” to start the PuTTY session.
Click “Yes” to dismiss warning.
 

You should now be connected to your instance.