Respect and warmth go a long way. You do not need to know every custom immediately—curiosity and good intent are an excellent place to begin.
Greetings
Take your cue from the other person, especially across genders. A warm verbal greeting is always a comfortable start.
Invitations and hospitality
Hospitality is generous and coffee may be refilled more than once. Accept graciously, and watch how others signal when they have had enough.
Dress with context
Saudi is diverse and increasingly relaxed, but setting matters. Choose polished, modest clothing for government offices, professional meetings and traditional spaces.
Yours truly,
Saudi