How to create .appxupload for created appx using makeappx tool?

I have created appx for .Net Desktop application using makeappx tool.I had used this command to generate appx: makeappx pack -d "C:\Centennial\PackageLayout"-p "C:\Centennial\Output\HelloCentennial.appx" The package creation is succeeded and I am getting output as HelloCentennial.appx.The windows app certification kit test also passed. But When I want to upload it on windows store it asks for .appxupload file. I know .appxupload is a zip-file contaning the .appx package and an .appxsym file.But I don't know how to manually create it or generate it using MakeAppx tool.It would be great If anyone can help on this.