It works fine for me. I think part of the problem is that your reading it too literally. That's not your fault; the instructions don't explain its own syntax very well. Here's what I did:
git config --global alias.hp help
Notice how I didn't just write "alias.<alias>" or the like. The whole purpose of the config command is to actually configure how git works. The point of alias is to give all your commands like config, help, init, etc. new ways to be called upon.
In the above example, I typed right next to "alias." what I wanted the NEW command to be, and a space away on the right where it says "help" I refer to the command I want to make an alias for. I'm basically changing the "help" command so I can use it just by typing "hp". You can literally make it anything you want. I could use code like this:
git config --global alias.IMABigBaboon init
and I can write IMABigBaboon instead of init and it will work. Try it!
Just be careful you don't name two commands the same thing. Otherwise you wind up changing the name of the previous alias. Remember; you can only have one alias for one command!