If your web host only allows FTP access and not shell access then you have to edit files locally and then upload them. If you are debugging your website that means making a lot of changes to a file or files and lots of manual uploads after each change to a file. FileZilla works great to upload and download files to a remote FTP site and it even allows you to set a default editor so you can right click on a remote file and click view/edit. It then downloads the file to a temporary directory and monitors any changes made to the file. When it detects that you have saved the file, it pops up a dialog box asking if you want to upload the file. Instead of having to manually switch to the FileZilla window and click the button to upload, you can automate the process with an AutohotKey
WinWait,File has changed
ControlClick,Button2,File has changed
The first time you attempt to upload a file that exists, another window will pop up asking if you want to overwrite the file. I recommend telling it to always overwrite the file so you don't have to be bothered with this window in the future.
This is just one example of using AutoHotkey to make your life easier. Enjoy!