Point at one of the handles, hold the mouse button down and drag to resize the field. Do this for all the fields. To move a field, point inside the box that defines the field, hold the mouse button down and drag the field to a new position. This sometimes takes a bit of practice. If you look at the sample above, you can clearly see the size of the label as a box.
Body defines the lower left hand corner of the label.
Look carefully at the row that contains City, State and Zip. Notice that the left and right edges of the fields do not quite touch. Then pull the Format menu down to Font, Size and Style to set the appearance to your taste. It is usually a good idea to center the fields vertically in the middle of the label, rather than at the top or bottom of the label. This allows for variations in printers.