This is one of the absolute first steps that need to be taken when looking to become a homeowner.
A budget is the foundation of your finances along with your credit. The best thing you can do is learn to break down your finances so that you know exactly how much money you bring in and where all your money goes.
Once you have an idea of what you bring in, you then can focus on where it goes, and how to set yourself up to buy as quickly as possible.
The sooner you start paying a mortgage, the sooner you stop making your landlord rich!