The most convenient public transport is bus service 27 or 28 (timetable Western 33). The 28 will bring you closer, but the 27 may be more convenient. Both buses run every hour, in both directions, between Claremont Station and East Perth. To be at the WABA meet from the very beginning:
From the east, catch the 27 that leaves East Perth at 10:15, or the 28 that leaves East Perth at 10:00 and passes Perth Station at around 10:08.
From the west, catch the 27 that leaves Claremont Station at 10:30.
You may wish to consult the full timetables: from Perth to Claremont; from Claremont to Perth; full timetable (Western 33).
