Near the stadium you just ask for the "roullotes", the beer is very cheap and for bonus you win a great Bifana (pork sandwiches)
If you want bars to go out at night I advice you to go to Bairro Alto or maybe Docas!
Go for Docas, you will find cheap Brazilian and Indian whores.
Watch out for AIDS.
Don't use condom.
It might make little sense, but it does in fact make little sense.