Arrival time: it's advisable to arrive at the bus station, 30 minutes prior to the departure time to avoid inconveniences.
Rio Main Bus Station: Rodoviária(Terminal) Novo Rio bus station is where you board your bus to Sao Paulo.
Terminal Tietê Bus Station in Sao Paulo is the destination of the bus.
there's always a bus every 15 minutes. so don't panic in case you miss your bus.
TRAVEL COMPANIES
Itapemirim
Expresso do sul
The buses are very comfy and stylish and so you get to enjoy your ride with minimum fatigue.
For safety purposes, I recommend not to walk to the Terminal Novo Rio Bus Station as its located in an unsavory area of the city. The bus station is safe though.
It's advisable to board a bus that'll take you to the bus station.
You could also board a bus at the Rio International Airport preferably, a shuttle run by company Real, which connects the airport to the bus station.
Also, make sure you are on the right bus, as the destinations of the buses differ. In case of doubts, ask the driver.
Luggage safety: there's a luggage facility at the Novo Rio bus station which charges about R$5 per piece. The charges may differ depending on the weight of the luggage.