You would need to purchase the Pro Tools TDM 6.9 Upgrade from the DigiStore or your Digi dealer.
That's a full installer, so you would install that, then the install the 6.9.2 Update. No need to install 6.0.x or 6.4.
Later this month, the 6.9 TDM Upgrades will have the 6.9.2 CD included, but in the meantime you can just download the update.
Upgrade & Update information can be found here in the Pro Tools TDM 6.9.2 Q & A on the 6.9.2 TDM Mac download page:
http://www.digidesign.com/download/692/hdmac/#qa