C drive is full. How can I extend C drive without losing data on Windows 10 PC?

When it comes to extending C drive on Windows 10 computer. One mistake I used to make was just deleting stuff without checking what’s actually hogging space. I can’t tell you how many times I’ve deleted a project file instead of that giant temp folder!

Tip: Use WinDirSat or the built-in Storage settings (Settings > System > Storage) to visualize what’s eating up space before making any deletions.

I used to think that window cleaners like Disk Cleanup were a one-time deal. But those temp files and caches just keep piling up! Ignoring them is like leaving dirty dishes in the sink—nobody wants to deal with that later.