Move Installer folder from systemdrive to save space (SSD)

Windows use space on systemdrive for almost never used installation files. You can easily move those from your expensive SSD to a cheaper datadisk:

Run cmd as Administrator, and use the following commands:
mkdir D:\Junctions\C\Windows\
move C:\Windows\Installer D:\Junctions\C\Windows\
mklink /J C:\Windows\Installer D:\windows\installer

You can also free up space by:

Disabling hibernation, the hiberfil.sys.

Deleting C:\Windows\MEMORY.DMP file

Deleting Java Cache (Java controlpanel, General, Settings, Delete files)