gedthehed09 wrote i go on my hardrive and move my profile to the usb and then take the usb out of the xbox plug it into the laptop and nothing comes up when i open the usb so like where my profile so i can mod it by the way people its my first time ;)

thats normal , it shows not up ( sorry for my bad english^^)
go to usb explorer there it will find and u can mod ur gt , if need help i do it free via teamviewer.

- ExoTiKz

Firstly You'll need a few things, If you don't have them already:

1. XTaf Explorer - This makes your USB device openable.
2. Modio - This is required to "ReHash & Resign"
3. Ez Gt - Required to change your GamerTag.

Okay, You said you've already put it onto your USB.

Now open XTaf Explorer and click "file" > "Open Device" > Click "Content" and then go right th way to your Profile number. Click "Extract" and extract it to your desktop.

Now open Ez GT, click "Open" and find the file you extracted to your Desktop.
Edit the gamer profile and click the "Options" tab and change the "Modded Profile Number" to "1".

Save to Dekstop and a new folder should appear, You can now close EzGt. Open up the folder and find the new Modded Profile. Drag and Drop the Modded profile into Modio.

Click "ReHash and Resign" and wait until it says, "Xbox360 DashBoard" then close Modio.

Now go back To XTaf Explorer, And go back to Content, Click content once, and the Drag and Drop the Folder that was created onto the Desktop.

Now Pull out your USB Drive and Head over to the Xbox.

Go to Xbox 360 DashBoard and Just transfer both Profiles back onto the Hard Drive.

Open Up MW2 and click Multiplayer > Sign onto the Modded Profile, It will ask you to create an Avatar, ONLY PRESS THE XBOX360 GUIDE BUTTON! ( The Central One )

Now It'll ask you to log onto a Live account, and Just log onto Your Real Xbox360 Profile.

Hope That Helped. + Rep for typing? :]