There are a lot of system stuff that just eat important space in Windows on disk C (if you have SSD and smaller C partition you don’t want to run out of space).
The best way is to create a junction (symbolic link) and to move some big folder to another partition (you need to have one first).
By doing this Windows will be fooled because you will get the same path but it will be shortcut (pointer) to another real location.
To do this move completely chosen folder to another partition and create symbolic link like this:
mklink /j c:\windows\MyMovedFolder d:\MyMovedStuff\MyMovedFolde