The following is a timetable using buses operated by EVA Transportes which will get you from Faro Airport to Salema on a Monday in September.
Faro Airport 10:47
Faro Bus Station 11:05 Bus 14 or Bus 16
FARO Bus Station 12:30
LAGOS Bus Station 14:40 Daily
LAGOS Bus Station 15:10
SALEMA 15:42 Daily
Regretably, there is no combination of bus or train that would allow you to travel from Salema to Faro Airport on Monday to arrive by 08:15.
It would have to be a taxi at about € 90.00 or you would have to travel down to Faro the night before and spend the night there.