Patent Law

I have an invention that I'm sure every new mom would love.  I've been told that the first thing I need to do is get a patent on it.  I have no clue how to do that.  A friend told me I need to hire a lawyer and that it will cost an arm and a leg.  I don't have a limb to spare so I don't want to do that if I can help it.  Is this true?  Can you get a patent on an invention if you don't have a lawyer?