Hi
You need a CELTA certificate if you want to be taken seriously
You might then have a very small chance of getting a job at a school like Cultura Inglesa
I must stress SMALL chance, theres no shortage of Native speakers here in Brazil who already have legal documents to work here, and also an abundance of highly qualified and very skilled Brazilian teachers in SP who you will be competing against.
These teachers already understand the culture and have attended English classes since they were little kids so they know exactly what to do...
Salary at a school like this is r$4500,00
Most other English schools you will be lucky to make over r$2000,00 per month
and if you are working illegally they wont pay you much.
Sadly English teachers are not well paid in Brazil and also the days of walking into a school and getting a job straight away as a foreigner are coming to an end.
The English school industry here is in Crisis and steady decline due to many factors.
Students here are seeking out other ways to learn like online classes , private teachers, exchange programmes and immersion weekends
Bear in mind São Paulo is almost as expensive as New York at least with food and entertainment. Rent is cheaper. You can find cheap options but if you go to a nice bar or restaurant expect to blow about R$100 + in a night - when you compare this to the low salaries here, especially in the English field it's very expensive!
It takes about 1 - 2 years to get Established as a private teacher here to get a few connections and a roster of private students (especially as you are not yet an experienced teacher) -
Private classes are the only way to make any real money teaching English here.
I guess you don't need experience to do this, but it certainly helps as students can pick up if you don't know what your talking about.
Portuguese is a huge advantage for explaining, making connections with students and teaching basic levels, you will be at a disadvantage without it, also bear in mind that most of the "Business side" (meetings etc) of schools here is conducted in Portuguese too.
I came here almost 3 years ago , with permanent residence so I could work legally. With an intermediate level of Portuguese and zero teaching experience.
I started at the bottom with the worst school in town and rapidly worked my way up to the best school, Now I only do private classes on Skype, I have some Brazilian students and teaching online classes for a Chinese company to kids in China. I also go on immersion weekends just outside São Paulo one weekend a month.
It took me 1 and a half years teaching classes at schools before I really started to feel comfortable as a teacher here.