To find the height, find the blocks inside the shape that is completely attached (they have to be in a straight vertical line). In this case, you can see that three vertical blocks in the middle of the shape is completely attached. That means your height is 3.
To find the width, look at the how many horizontal boxes make up the top. 6 block inside the shape corispond with 6 blocks on top of the shape, so the width is six.
