How to connet HTC TyTN under disk mode???

My phone is HTC TyTN.
I wanna install app on my phone but the activesync mode installation will take more time. So I try to connect the phone with PC under disk mode but every time I connect them via usb it's avtivesync mode. Where can I find the disk mode?
Anyone can help me?

I didn't own HTC TyTN, but I guess the connection is the same with other phones. Go setting>connection>the massive storage. The next time you connect it to the PC, it will be detected as a disk.