Upload my iphone app to app store

I have just designed an iPhone application but am having trouble uploading the .app file to the app store. I am getting an error that states the binary has not been signed with a valid distribution certificate. I need someone to log in to my itunes connect, upload the binary to my already open application and then outline the exact steps taken to make it happen so that I won't run into that problem again. NO CODING IS NECESARY. THE APPLICATION IS ALREADY WRITTEN. JUST NEED SOMEONE TO WORK OUT THE CODESIGNING ISSUE. THANKS.