Never spend more than 3% of your gross income on consumption.
That is, food, rent, cars, clothing, etc. Invest 97% preferably in your own little side business.
Most people would say that it would be impossible to save and invest 97% of the salary when we could barely get along spending 100%.
Look for the spending cuts in every area of your life. Instead of paying retail rent, get a part time job managing a building in exchange for a free apartment. Food? trade services for free eats. Like paint some pictures, put them on the wall of a restaurant for sale. Learn a few portable trades & occupations. Car? Get rid of the “new” one with payments and get a used, cheap, dependable one.
By the way, spending only 3% is a GOAL. You try for that, and you will certainly do better than spending 100%…