Requirements:

  1. Head to https://play.google.com/apps/publish/ 1a) Create your developer account if you do not have one
  2. Click button Create new Application
  3. Click submit APK
  4. Fill in all required fields in the form, including some assets that will be displayed on the Play Store (see image below)
  5. When satisfied hit Publish app button

http://i.stack.imgur.com/t28JM.png

http://i.stack.imgur.com/S3lhQ.png

See more about signing in http://stackoverflow.com/documentation/android-gradle/5249/configure-signing-settings#t=201608060822323313637