First of all, they need more intellegince. Then they have to have speed and power, witch wern't accomplished during WWII most of the time. Then they need quick reinforcefents, because of their light weapons, they wern't very powerful and normally accomplished by sheer numbers. They also need to look at their options. If they are able to invade from land or sea, use that option. They also need air supremacey or superiortey. In Vietnam, the Koreans had no air force, so paratroopers were used a ton. In WWII, the allies had air superotiey, so they did have a little risk. In concluision, you really shouldn't use the paratrooper option unless you have superior technolgy and numbers, something the aliies simply didn't have during Market Garden.

__________________
The objective of war is to not die for your country, but to make the other bastard die for his! - General Patton
Older men declare war. It is the youth that must suffer. - General Patton