Jesus Christ, Oxblood. My whole life has been a blur. Since I got it Tuesday afternoon, I have spent 56 of the past 90 hours playing it. I don't know if I'll ever see color properly again.
Honestly, I just ran back and forth from area to area, pushing a little bit at a time in each direction, similar to how I did it with the different worlds in Demon's Souls.
I know that after the twin Gargoyles, I went back to Firelink and poked around in the Catacombs for a long time. I may have killed the boss there, during that push. Things there are weak against Divine weapons, by the way. After that, I went back to the smith, ran around the Titan, because I couldn't kill it yet, and I went into Darkroot Basin, exploring around there. The Hydra freaked me out, so I ran in the other direction and came across a Black Knighht standing in front of a tunnel. That tunnel opened up a bunch of things.
More than anything in this game, I love the sensation of falling down the ravbit hole, as it were - barrelling down a tunnel, constantky moving forward, seeing how deep and how lost you can get.
At some point, you'll probably need the Basement Key, unless you've got that Skeleton Key item. That key should be your next goal, after poking around a bit. I can't remember where to find it, but the info should be available online. My mind is going numb from the constant running. I'm Level 74, I think.