Wiping an iPhone or iPad is easy: go to settings and choose erase all content and settings. Or, connect the device to iTunes or Apple Configurator and click Erase and Update.
But there's a faster and better way: FileWave Lightning. It does clean installs of a Mac in 10 seconds over Thunderbolt 3 via Target Mode.
It's a tool I use on a daily basis while managing Macs at the company I work for. It's fast. Wickedly fast.
Steps to wipe your Mac
- Boot the Mac you want to wipe in Target Mode
- Open Lightning and press Deploy
- Select the mounted drive
- Press Deploy
How to Create the restore image
- Download High Sierra from the App Store
- Click Create
- Drag the Installer you just download into the Lightning window
- Image creation takes 10-15 minutes. (so yeah technically Lightning takes 15 minutes to reinstall a Mac, but your second one will be a lot faster!)