Create your own personal salesforce developer org

Step 1:  

Use an existing email or create a new one for your developer org signup. 

I am using 123sfdccloud@gmail.com . Now go to  https://developer.salesforce.com/signup

  

Step 2:  

Type your first name, last name, email address and user name on the form page.

Please note: User name should be in the form of email but not necessarily it should be a valid email. For example, I have used sfdc123mydevorg@gmail.com

Whereas my email is sfdc123cloud@gmail.com , so before @gmail.com you can basically use any lower or upper case characters, numbers etc.

Step 3: 

Read and accept the agreement and click on sign me up

Step 4: 

You will receive  login confirmation details in your email. Click on the link to confirm your account.

Step 5: 

Salesforce will ask you to provide some more details like password, security question etc. This will help you in case you forget your password later while signing in to your personal developer org.

Step 6: 

Hit Save and you are done!!!

Step 7: 

Now let us login to your brand new developer org. Open any browser and go to https://login.salesforce.com/

Step 8: 

Type in your developer user name and password, for example: sfdc123mydevorg@gmail.com. Now click on " Log into Salesforce" 

Step 9: 

Welcome to your brand new developer org. This is how your spring 15’ developer org landing page will look like, don’t miss the Tour of “improved set up”. It gives you high level basics of where to locate the following - Set up, My Settings, Administration pages, Build Pages, Deploy, and Monitor.