Go to the BT747-Sourceforge-page and download the current stable version. Unzip the content. Change to folder "dist", there you find the different distributions of BT747. Use
BT747.pdb
und BT747.prc
are for Palm PDAs, the appropriate CAB
file is for your Windows Mobile PDA. Install them using the software provided by the manufacturer of the PDA (or any other other method that you are used to).
Also you need SuperWaba. Download them from Sourceforge. There are again different files available, select that one that you need for your PDA and install this the same way as above.
To run BT747 just click in the icon. SuperWaba will automaticaly start in the background. If you prefer another language click on the titlebar and select "Lang", choose the language you like.