-To get infinite points, gain 9,999 battlefield points which will give you an unlimited amount of points to buy things with destruction on demand. Your points will never go down.
-To easily gain the 9,999 points needed for infinite points, play through the level you want to use it on, then save the game just before the end so that you have a lot of points. Then, load that game. It will start at the beginning, and you will have all of your points. You will also still have all your all your buildings. Go through the level and slaughter them to gain points quickly.