Lets start by defining your net income, this is the amount you earn after tax deductions.
Now to live within your means, you need to make sure that your monthly expenses are less than your income.
A good way to establish if you are living within your means, is to keep a daily record of where your money goes during a typical month.
Make a note of everything you spend each day, over a month. If you carefully track your cash outflows using a mobile app from your bank or other expense trackers on the app store, you'll feel more in control and will be able to see where your money really goes.
At the end of the month, add up all of your expenses and subtract this total from your net income. If your monthly expenses come to less than your net income, then you are living within your means.
Take time to reflect. If you aren't living within your means, don't worry. Start a deep dive into your expenses to see which ones can be reduced or avoided.