It will display your Wii U's IP address for you to enter into your PC's USB Helper application after you click 'Send to WiiU'.
Once done, go to the Downloaded list and select the games you want to install and click Copy to SD.Make sure you have a backup of this data and continue. It will ask you to format the drive which will erase all the data from the USB drive. While these games are downloading to your PC, plug your external USB drive into your Wii U while it is off, then power it up.
Once you've selected the games you want to download, click 'Download games'.
So on to the instructions, I'm not responsible for anything bad that happens, and never update your console past version 5.5.1 or you'll lose the ability to do this: I got a WD Elements 2TB and because the Wii U doesn't provide enough power from a single USB port, you'll need a Y cable. (Recommended)External USB Drive, up to 2TB.Computer with SD card slot and SD card(or microSD converter).Wii U with system firmware 5.5.1 or 5.5.0.Lastly, you install the games from the SD card to either the Wii U internal memory or an external USB hard drive. From there, you transfer them to an SD card which you put into your Wii U. Once the system is hacked, you can use a software called WiiU USB Helper to download eShop titles directly to your computer. As of right now, the current Wii U firmware version is 5.5.1 which is hackable.