You can move the calculators around on the screen just like you move normal windows. If you click and hold the mouse button on the top bar of the calculator and move the mouse, the calculator will follow. Just let go of the button to drop the calculator.
You can change the size of the calculator by clicking and holding the bottom right corner and pulling the mouse away. You may want to make the calculator wider if your commands are long, or taller if you have many commands.