How do you make a pyramid stand?
make it out of big bricks.
If the height increases what happens to the lateral sides of a pyramid when you decrease the size of the base?
3, if you stand on top of each other. No, really. One person can make a small pyramid in minutes. The pyramids of Egypt are special cases. They took many decades to build, and it took the labor of perhaps as many as 100,000 people or more to complete the largest ones. It might have taken considerably less than that to make some of the smaller ones; all we can do is estimate.
(Not sure if this is what your asking) The pyramid is an Ancient Egyptian tomb mainly for the pharaohs. They have many rooms to house the pharaoh in his afterlife. They were only built in the Old Kingdom. (There is A REALLY fun game on building a pyramid at http://www.bbc.co.uk/history/interactive/games/pyramid_challenge/index_embed.shtml)