There are so many ways to make a budget and no one way is wrong. Making a budget is, like anything in personal finance, personal. Some people just put away a percentage of their income and spend the rest. Others make maximum percentages per category, for example 25% of net income towards housing.
But when you are starting off the best way to start is to figure out where the money is currently going. Start by taking a month and writing down everything you spend and by the end, you have the beginnings of a budget. But you won't be done there. There are many annual or semi-annual expenses people forget about, like Christmas or car insurance or even car repairs. Start with the monthly expenses and divide what annual or semi-annual expense by 12 or 6 months and put that in your budget as well.
Now, the big question is after all your expense do you have any money left over? And if so, how much? If it is 10-20% of your income, great! If not, you are normal and it is ok. But you do need to work in retirement and emergency savings into your budget. That means looking at your other expenses in your budget and finding ways to cut them down.
It took me about two years to get my budget and my spending the way I wanted them and I still have some improvements to make. Making a budget is not something you do once and forget about, it is a tool for most of financial life.
Do you have a budget? Do you think it is helpful or not? How did you make yours?