I call it the FBS or Forward Base System. Basically, it starts out with a main base. This base will be used for everything, and it will be huge! HUGE!
In mine, I have farms for everything, monster and animal traps in the basement, a skybridge, a real bridge, and best of all, the tunnel. Out of the back, just start digging underground. Make a tunnel large enough for an eventual minecart railway. You can use the stone you get to build the tower up more and prepare for your first forward base.
Once you tunnel out quite a ways, dig up and look at your surroundings. If you are in a good place to build a tower, start hollowing out the ground and building up a wall. This will be your first forward base, and will act as a place for you to return to if you get lost out in the wilderness. Generally, build these bases near a natural mine. Also, look for mountains to build it in, as this has a neat visual effect like one of mine below.
Eventually, you end up with towers all over the place making the wilderness much safer for you. Another way to do this is to go out and find a natural mine, build a tower around it, then connect your tunnel to it. Eventually, you may even want to connect them all by skybridge too, like I have in my first pictures.
Here are some cartographs of my region, where you can see the scope of everything. While tunneling, you can discover more natural mines and some very interesting things. Expect a tour of this system as one of my first videos which are coming soon.
