How to adjust MacBook Desktop icons size

To adjust the size of the files and folders icons on your MacBook Desktop you need to right-click on the Desktop and select the option Show View Options

Once you click on Show View Options, you will see a window wherein you can use the bar next to "Icon Size"

As you adjust the bar you can either increase or decrease the size of the icons, you can change the icon size to a minimum of 16x16 to a max of 128x128 (64x64 being the ideal size)