Hard points: where else can we "jack"?

I jacked my car up the other day to attempt to put in the safety clips for the EVOms CAI system, and though I was unsuccessful (I honestly don't see how they get them in without taking the bumper off or using a 'proper' car lift) I did manage to bend a point of my beloved GTI's underbody. Which brings me to my question:
Where else is it suitable for us to put the jack, other than at the 4 designated hard points just behind (and in front of) the wheels? How on earth (I've only tried once) do you get the car on 4 jack stands rather than 3 stands and one jack?!?!! It's really, really mind-boggling!
Thanks all--
AD