start/settings/connections/connection icon/manage existing connection/click edit/give a name to the connection/click next/nummber to dial #777/click next/username= your ten digit
number@mymetropcs.com/password= metropcs/ click finish/proxy settings/check both and the proxy server as wap.metropcs.net/click advanced, click on every protocol and add or create this:
HTTP: wap.metropcs.net port 3128
WAP: wap.metropcs.net port 3128
SECURE WAP: wap.metropcs.net port 3128
SOCKS :wap.metropcs.net port 3128
Click OK 2 times/click on advanced/click select networks/you'll see two drop down boxes select the name of your connection " MetroPCS_Net ", if you do not see that then select " My Work Network " (top) and " My ISP " (bottom) drop down box/ click OK/ go to main screen/try to open any web page, if you see RESOURCE NOT FOUND in lite blue color you have done it.
P.S. good luck, (Credit to FRED_DJ)