The 'apéro' (apéritif) — drinks and small bites before dinner — usually starts around 6:00–7:30 PM.
Order a kir (white wine + cassis), pastis, or a glass of rosé. Olives, charcuterie, and cheese are typical accompaniments.
Many bistros have an 'happy hour' (in English) from 17:00–19:00, with reduced drink prices.