Pyramid.
having made a trade and seen the trend in your favour
you add another trade and then another and another.
so on a 100 pt move on the index you can net say, 150 pts even if you dont get in at the beginning of the move and also get out before the end.
the first pyramid ( second trade) is the tricky one.
you need to place it at a point where if the market turns against you, you can close out both but with a small profit.
Never let a profit turn into a loss !
The next trade (third) is easier because your stop is the entry point for the second trade and the profit from the first trade is 'locked in'. so you should be protected.
then its up to the market. If the trend continues, you add again
until eventually you run out of margin.
but your margin is all profit.