The only advice I can give to people is
Don't use programs or other methods that affect your upload speed, makes you delay.
Don't download games or movies/whatever, that makes you lag.
Try to keep your connection clean. Between 2000 and 4000 players, your ms shouldn't have a difference of more than 100, if it's more, then you need to "tell your parents to" stop using a lot of bandwith.