Aperture, Shutter Speed, ISO... Arghhhhhhh

I'm pretty sure that I actually understand the 'triangle'. I've read Understanding Exposure by Bryan Peterson (great book, highly recommend). It all makes sense to me. But when I have the camera in my hands, it just doesn't happen. I dial in numbers, get a correct meter reading, yet almost everything I shoot seems underexposed (that and out of focus). When I overexpose to compensate for that, I end up with blown areas somewhere. ~sigh~

Today I took Piper outside again. I swear, my house has the worst yard for backdrops. Yesterday I took her out so I could play with parametres and I had to bribe her with chocolate! Today she did it for free. Anyways, this photo was the best of the bunch.