Enfold child theme

So I am running a child theme on Unicornfitness.com, I got it from the feature you guys added into Enfold. I want to learn to edit the css myself. I see there are css files in the parent folder of the child theme. What would be the best way to edit these? Should I download all the files individually and use Hostgator’s ftp to upload the changed ones? Is there someway I could download the whole current child and parent theme I am using from my site so it has all my settings and etc. I want to play with the numbers with things like those lines under the main menu so I don’t have to bug you guys. Thank you.