You need:
a) A font with the ligatures properly defined.
b) A reader which can use ligatures defined in fonts. I believe the latest ADE version (preview?) can.
Otherwise, the text does not need anything special, just write "action" and "office" with 6 letters each, the "ct" and "ffi" ligatures should be automatically used. Unicode has slots defined for some ligatures... do not use them, just rely on the font.
In my Orizon reader, with the Minion Pro font I can see the ligatures in "fi" and "fj", and I bet I would see "ct" and "st" if they were defined in the font.
This font claims to have many ligatures, maybe not exactly the ones you want, but I guess you can use it to test if the reader is using the ligatures.