Great job deciding to connect your website to a domain! It shows you really do mean business.
Now you need to make sure you own the domain name you want to connect to your website. If you don't own the domain, please scroll down further to choose and purchase an appropriate domain. If you already own a domain, please make these 2 changes in your DNS settings (should be found on your registrar's account):
1) Add an empty (@) A record with the value 34.96.116.138 (delete any other A records you have)
2) Add a 'www' CNAME with the value of im-router-service.com (without the http:// prefix)
If you are still not sure what to do you can just forward this information to your domain registrar and ask them to make the changes for you.
Click here for a more thorough guideline with links to instructions on changing DNSs in most of the popular registrars.