How to Customize Your Salesforce Login Process with My Domain?

My domain :

My domain is a salesforce identity feature that let you personalize your salesforce org by customizing your login URL.

Reasons to register My domain :

You can add your Company name or brand name to your login URL.
You can Show your company logo or brand logo on the login page.
Let your user login with their social-networking credentials such as Google, Facebook.
You can use Lightning components in Lightning component tabs, quick actions, Lightning page, the Lightning App Builder or standalone apps.

Steps to register a custom domain :

Go to setup and enter ‘My domain’ in the quick find box and select my domain.

2. Enter the subdomain name that you want to register. Keep following things in mind while entering the subdomain name :

a) It should not contain reserve words like – www., Salesforce, Heroku.

b)It should not begin and end with hyphen(-).

3. Check for the availability of the subdomain name you entered. If it is already taken enter a different domain name.

4. Register domain.

5. Wait for an email from Salesforce with the subject ‘salesforce domain is ready for testing’. open the link from the email to login back to Salesforce.