You can upload it to a subdirectory for testing/development. Unless someone knows you have a website, how can they find it? Plus if you have a question or problem, none of us can look at it if it's not somewhere on the net.

I use the files on my local drive to copy/edit the files I need and then upload those to the domain where I'm testing.

In addition, there are ways to set ZC up to run locally. Take a look in the FAQ/tutorials and see if there's info on that.