When you hear about WADs, people are talking about files with the file extension "wad". WADs can contain a lot of data. Mostly, this data is a channel or IOS file. It might be handy to know how to install them.
1. Download the WAD manager and extract the pack to your computer, then copy the apps folder to the SD card, merging it with the existing apps folder.
2. Put the wads you want to install in the "wad" folder on the SD card/USB device.
3. Run the wad manager. If asked, select IOS249 for IOS to use (IOS236 may also work if you have it installed).
Select Front SD card as the source to load the WADs from.
If it asks about NAND emulation, leave the option disabled.
4. Go to the WAD you want to install and press A. Then follow instructions on the screen.