Get a map. And download the metro map. But you should probably plan on taxis for convenience. It’s a big city. And it feels so. Also, you’re not going to be able to do all of that in one day.
Try this map: http://www.maplandia.com/brazil/sao-.../vila-mariana/

MASP is on Av. Paulista which is Jardins. Lots of shops and restaurants, and the lush Trianon park nearby. I could probably happily spend the whole day there, just wandering around, visiting coffee houses and bookstores. There is a metro stop near the park.

Pinacoteca museum is near the Ibirapuera park, another sight to see if you want (although not as nice as Trianon IMO). Also visit neighborhood shops of Vila Mariana.
Jardins is a little northwest of Vila Mariana.
Liberdade is a little north (a bit more than Jardins) of Vila Mariana. Japanese and other Asian restaurants and shops.


Banespa is open 10-3 M-F (João Brícola 24)
Edifício Itália (Av. Ipiranga, 344, Republica neighborhood) There’s an expensive but good restaurant at the top too. 4-5 pm for free viewing deck iirc—coffee shops on ground floor

Neighborhoods are accessible by metro or taxi.

Note: I am not particularly a Sao Paulo mavin.