I noticed @Sarcasm has unneeded steps in the tutorial he made so I decided to make this one because you don't need to download anything or put in any numbers.
Step 1: Click tools then options.
See below:
Step 2: Click advanced, then connection.
Step 3: Make sure "Allow direct connections..... only" is checked.
I used a similar tutorial from leakforums, it seems to work with the HWID changer and shit. Pretty nice, I'll show this to a few friends of mine to make sure they understand the easy side of life.