I run an e-commerce site running a php shopping cart system. The way the shopping cart is structured is admittedly a bit complicated, which makes me nervous when I push live updates to the site.

Currently, I have a hosted dev site where I make changes, and when I'm ready for a release I manually change the files in the ftp. Not the best solution, especially considering a high chance of user error.

What is the standard practice for pushing updates? Git would make more sense, but implementation seems daunting. Any advice is appreciated!