Live Site and Test Site?

[eluser]Rok Biderman[/eluser]
Well, the safest way to not mess anything up is to have a test site. If nothing else, your changes are probably going to affect the db and if anything goes wrong good luck finding out which changes are yours and which were made by other users.

If you use some kind of version control (i.e. Git), it's very easy to maintain two separate branches, one of which deploys to test and another to production (using git-ftp for example). Once you're satisfied with everything, you just merge into production branch nand redeploy to live site. It's an investment in time but it can save you a lot of confusion later on.