I moved out on my own when I was 18.
With the money that I made from the companies I started, I decided to move away from home and explore life without their help. The new sense of freedom was amazing, until I used up all my money.
1. Learn to budget and reduce your expense
Budgeting helps you eliminate unnecessary spending. It is important to do this once every few months or as your income changes. After you budget, set a goal (retirment, buy a house, etc)
2. Build an emergency fund
An emergency fund should be a relatively liquid sum of money that you don't touch unless something unexpected comes up. Save enough to help you survive 3-6 months.
3. Pay down high interest debts
Use your extra money to pay down your high-interest debt (e.g., debts much over 4% interest rate).
4. Maintain a good credit score
If you are a student, most banks offer a 1-year interest-free credit card. Take advantage of that and use it to make small purchases, and pay it off on time every month.
5. Don't Change Your Lifestyle Based on Your Current Income
A lot of people make the mistake of spending more money and living more lavishly as soon as they are having higher income. This is dangerous because incomes are volatile.
6. Put 10% in Savings
Not really a general rule, but personally I would put 10% of every paycheck to my savings account. It seems small, but it slowly builds up and can act as an emergency fund.
7. Check to see if you are eligible for tac deductions
You may qualify for tax deductions if you spent money on taking classes, your hobby, and many other things!
8.Don't lease or rent things unless you have a steady income
Leasing or renting means being committed to paying for it for years down the road. If losing your job means that you won't be able to pay for it anymore, perhaps you should seek other options.
These are all the things that I learned from my mistake
Hope that help you!