If you would like clippy to let you know you are low on mana (<25%) and this should work for all healers (only), you need to use the string above and import that into weak auras.
After importing, you need to create the following folders, and import a clip (mp3) and icon (tga) into their respective folders.
Create a folder called "Icons" in the retail\Interface\ folder (reads like, "retail\Interface\Icons").
Create a folder called AUDIO and then a subfolder called "clippy" in that same area (Interface) called (reads like "retail\Interface\AUDIO\clippy").
Should be able to drag and drop the zip contents inside the _retail_ folder.
You need to close WoW completely.
Download can be found here
https://drive.google.com/file/d/14PixhSlCMWHjmHwfMPYuluQCgBPkXzqi/view?usp=sharing