Budgeting your money.

Do you have a formal budgeting process for managing money you make ? Or you just keep it all in your head like me ?
I read a lot about how important it is to manage your money and keep tabs on what you spend it on. They emphasize that you should use pen and paper or in todays world use a software to manage your money. I could never get to doing this. Being a desi I have inherent instincts about where , how , what should I spend my money on. I do not see any need for a formal money management process.
What is your take on this ?