Uninstall whatever client you're using now, which will be the standard BT 3.3 for most of you. Then download this: Azureus.
Then when you open it, configure it to your max upload speed, then test your ports (most important). Make sure all of them work! 6881-6888 i think are the defaults, after I tested my ports on azureus I found that 6881 wasn't working but the rest were. So I switched it to 6882-6889, and they all worked. Now I am dominating BT, maxing out my connection on download!!
Then when you open it, configure it to your max upload speed, then test your ports (most important). Make sure all of them work! 6881-6888 i think are the defaults, after I tested my ports on azureus I found that 6881 wasn't working but the rest were. So I switched it to 6882-6889, and they all worked. Now I am dominating BT, maxing out my connection on download!!