After getting used to the concept you can start to play different games like capture the flag, elimination, ammunition limits, defending or attacking a particular point or area, or capturing objects of interest hidden in the playing area. These games can last anywhere from a few hours to days depending on the league, game, and limits. Although there can be set rules they vary game to game. These rules are stated before the beginning of the match and should be followed throughout or you could be kicked out. If you aren't too fond of rules just play in the woods with your friends.
It doesn't matter who you are this is something I greatly encourage all of you to try. The adrenaline rush during a match is so incredible that it's seemingly addicting. I live it so much that I'm saving up for my own paintball gun so playing recreational matches will be far cheaper. I encourage all of you to do the same. Below is a quick video I found showing some paintball in action. Enjoy and thanks for reading!