Look up the date of Carnival before you book Rio de Janeiro for February. It ends on Shrove Tuesday, so it moves with Easter and can land anywhere from early February to early March. If it falls in your dates and you want the party, you have picked the right month. If you want quiet beaches and fair hotel rates, stay away from Carnival week, even if that means coming in another month.
Book your room the day you decide. Ipanema and Copacabana put you near the beach and the big neighbourhood blocos. Centro is closer to the Sambadrome but empties once the offices shut.
Pick your nights at the Sambadrome. The Special Group schools parade on the main Carnival nights, in recent years Sunday to Tuesday, four schools a night from late evening until dawn. The Série Ouro, the division below, parades on the Friday and Saturday before, with tickets at a fraction of the price. They sell out as well, so buy early. Miss the lot and the Champions' Parade on the following Saturday brings back the top schools. Buy through official channels and take the metro.
The street party costs nothing. Blocos, neighbourhood parades with their own bands, start weeks before Carnival and carry on for days after. The city publishes the official schedule on its carnavalderua.rio site and app. On Carnival Saturday the Cordão da Bola Preta, the oldest bloco still parading, fills the streets of Centro from early morning.
Expect highs around 30°C and rain on about 13 days. Do the blocos in the morning, retreat for the hottest hours and head out again after dark. Carry a light poncho: an umbrella is no use in a packed street.
Snatch theft rises sharply in Carnival crowds. Go out with one card and a little cash, keep the phone in a front pocket or a cross-body bag, and leave everything else in the hotel safe.