Start by planning your essay. How many different uses of math do you need to include? How much detail is required?
Once you have some ideas for the applications you're going to list in your essay, you can start writing. Your first paragraph will introduce your essay. Your thesis statement will probably state that math is used every day in so many ways that we don't even notice most of them. Then you could briefly list the uses that will be more fully explained in the body of your essay.
If you're going to talk about using math to track the money people earn or spend every day, you will want to provide examples of expenses that people face - paying for lunch, buying gas for their car, charging the cost of new clothing, and so on. To cover these costs, people need to receive paychecks or tips or lottery prizes or birthday presents of cash.
Another paragraph might talk about how uses of math shape the ways in which we live our everyday lives. We check the weather forecast to learn what the high and low temperatures for the day will be before deciding what to wear. If we're going on vacation, we consider the number of miles we'll drive today when packing snacks to eat in the car or before making a motel reservation for the night. We keep track of the time to make sure we remember appointments and we check attendance at meetings to confirm that everyone is present. If we're cooking dinner at home, we use measuring cups to assemble the ingredients of the recipe and monitor the baking time and temperature in order to have the dish turn out well.
Other paragraphs could address other uses. Your final paragraph would then summarize all the uses mentioned in the essay and restate your thesis, that math plays a central role in our daily lives.