It is easy to control personal expenditures. Go to the bank, ask them to take 15% of the income, and forget it. Either way, you will be broke, right?
Then download an app to record your spending, such as:
Next for iPhone by noidentity gmbh
This app will record all of your spendings; by the end of every month, you will know how to reduce your spendings. I discovered that I spend 2000 SR on grocery stores for Red Bull, ice-cream, juice, and nuts, they are not important, but I got used to buying them before going to work or university.