Changing icon size on your Desktop in Windows 8 works the same way as previous versions of Windows, so how do I change their size? the solution is simple.
Also use the Screenshot below for visual help.
Step 1. Right click on an empty space on your Desktop.
Step 2. Select “View” option at top
Step 3. You now have three options for changing icon size: Large Icons, Medium Icons, Small Icons (Classic Icons)