After Placing bones, you'll have to bind the skin(the dog) to the bones. You'll have to adjust the weights, these control how much influence each joint has on the mesh by painting in its intensity that it has on an area. this is very cool, because Maya lets you use a brush with varying phases of softness to paint your influences. Its one of my favorite parts of animation. This part can get very complicated pretty fast, but for what your doing, your probably just going to switch to animation mode>skin>bind skin> smooth bind. As far as you setting go, I use bind to selected joints for starters, leave the rest as is, but you can play with the settings here and see what works how. To paint weights, you'll want to go to..skin>edit smooth skin>paint skin weights tool. Theres alot of room for experimentation here. The idea is to paint on the influences and fade them to less influences, and move the model alittle to see how the skin deforms. You can adjust the weight a joint has on the skin which in turns, adjusts how it deforms. Its alot of trial and error and, you'll see if your model needs any more work. Play with it, and have fun! Hope this is alittle help.. I'm a newbie so I'm learning as well.