To create a new store account, visit https://dev.windowsphone.com/en-us/join and refer to the following steps:
You will need a Windows Dev Center account for this, but don't worry, you can create one after clicking on the Accept and Continue button. To create an account, you need to have a credit card or a token that is given to you if you are part of the BizSpark or DreamSpark program.
In the next step, you will be asked to enter or create the Windows Dev Center account. You can keep the same login and password that you use to get into any Windows OS.
Once inside, you will be asked to select an account type. If you are an individual developer, you can choose the individual account; otherwise, select the company account. If you select the company account, keep all the details regarding your company ready, which you will need in order to fill up the details and finish up the registration process:
Select Country/region and then select Enroll Now. I have selected Individual...