When you get to five, make them into a continuous ring of five. Then start working out from there. Always make sure the pyramids are in rings of five. Eventually, the whole thing will close up on itself and make a beautiful stellated icosahedron! Theoretically, the whole thing should hold together without any tape or glue but you can cheat by taping it on the inside where nobody will see once you are done.
Just for fun, can you figure out how to make a nice little cube using the same folded pieces of paper?
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