Lagos is informal in many ways and formal in others. A few habits mark you as someone who has made an effort, and smooth almost every interaction.
Respect for age
Age and seniority carry weight. Greet older people first, address them with a title — “Sir”, “Ma”, “Mummy”, “Daddy”, “Aunty”, “Uncle” — and do not use their first name until invited. Younger Yoruba people may kneel or bow to greet their elders; you are not expected to, but a respectful nod goes a long way.
Hands
Give and receive things, especially money and food, with your right hand, or with both. The left hand alone can seem rude.
Visiting a home
Take off your shoes if your hosts do, accept the drink you are offered, and expect food. Bringing something small — drinks, fruit, a pastry — is appreciated. Greet everyone in the room.
Dress
Lagos dresses well. Neat is respectful, especially for offices, banks, churches, mosques and government offices. Cover up at religious places.
Photographs
Ask before you photograph people, and never photograph military sites, police or soldiers, or government buildings: it can lead to trouble.
Haggling and saying no
Haggling is expected in markets, and good-humoured. A direct “no” can seem blunt; “let me think about it” or “next time” is the polite way to decline.
Time and patience
Social events start late; work does not, in a well-run office. Patience and good humour in queues and traffic are the most useful Lagos manners of all.