Geneva is 6 hours behind Jakarta
Best overlap: 2:00 PM to 6:00 PM in Jakarta is 8:00 AM to 12:00 PM in Geneva.
2:00 PM to 6:00 PM in Jakarta is when Geneva is also working, at 8:00 AM to 12:00 PM their time. You've got a decent 4-hour window. Set a recurring time near 2:00 PM in Jakarta (8:00 AM in Geneva) and stick to it. Watch the DST gap — when Geneva changes its clocks and Jakarta stays the same, this window slides by an hour.