How do I deploy a source bundle to Elastic Beanstalk on AWS?

Question

I've created a .zip source bundle that's ready to use in Elastic Beanstalk - the problem is that I've created this in SSH and I have no way of being able to access the .zip file to upload it in the "Choose File" Dialogue that opens when I click upload in the Elastic Beanstalk management console.

I'm following this tutorial from AWS. I've looked at various searches along the lines of scp'ing it to my local machine, to then upload it or even copying it to S3 to then download it, to then upload it. So far though, I can't find any step by step way of doing any of this and am completely stuck in the mud.