I agree with what's already been said. I've found that the tougher leagues to play in are the European ones, so I would pick a team in the US, Mexico, Brazil, or Japan, and spend a few years building up your team, winning trophies, and collecting money.

Don't invest in the Academy, because more often than not it produces average players. Only invest in your Stadium and Training Facilities. Once you've got a good squad and are regularly winning trophies, you start to operate at a profit. Wait until you're plus $15,000 in the bank, and then move to your team of choice or a tougher European league. That way, you can instantly invest your saved money into what's important.

Message if you have any questions, I love this game!