XAMPP trouble

[Kesstryl]

I can upload scripts to my webhost, install, and run them just fine, but I've never been able to get Xampp to install anything. So far I've done the unprofessional thing of applying changes to my code, uploading it, and seeing what happens. If I do get a site running with people actually using it, this will become a problem. I've followed Xampp's instructions to place files into the htdocs folder and then access them from your browser in your localhost, which I did with Mysidia, but when I try to install, it says the URL can't be found. There must be an obvious reason why this is happening, but after hours of searching and googling, I'm hoping someone here who also uses Xampp might be able to help. If not, what can I download instead so I have a place to pre-test changes before uploading them to my website?

Thanks