The idea of these hills is that you layer them with logs, then branches, then leaves, then dirt, then leaves, then dirt, then manure, then compost, etc. More or less, like a lasagna of organic debris that will decompose, absorb water, and feed your crops (sometime down the road). Not only do these hills produce beautiful produce, they also are quite nice to look at.
In my opinion, these hills are quite compatible with the suburban garden, as they are aesthetically pleasing and easy to maintain.
So, how do you start? You collect some trunks of trees. People are cutting down trees all the time. Before you have ever built a hugel, you don't think much about it, but once you've built one, you start seeing the felled trees everywhere... trust me.
I helped a friend to take down one of her trees and I got materials for my hugel and she paid me some money to boot! Then, you roll up your sleeves and start digging.
After you have layered your biggest trunks you continue with a layer of branches.
PS: Some people say cedar wood is a no-no for hugels, but I have to say that they probably have not ever tried it. The hugels I made with cedar wood are doing fantastic when compared to the other types of wood. So, if life gives you cedar wood, make a good hugel out of it.