Actually there are two ways to go, the most common method in the US (EU and Japan) seems to be to try and wring maximum efficiency, out of their systems and designs. Unfortunately, going for the cutting edge, is a big part of what tends to make getting to orbit a pretty expensive venture. There is another direction that was somewhat pursued by the old Soviet Union (at least a some points in their space program) which involves not worrying so much about designing for maximum lightness and efficiency, but rather overbuild with bigger engines, and higher mass fractions resulting in larger overall launch systems putting a smaller percentage (but equivilant) of its overall mass into orbit as payload. The payoff is significantly cheaper systems that are easier to manufacture, and generally more simple in function. Its been studied and whitepapered to death for those interested, you might check out the "BDB (Big Dumb Booster)" systems and/or the "Rocket a Day" systems.
