A surefire way of doing the wrong kind of things is to spend your money early or try to live a good life quickly without thinking about the future. Or if you have an ok job or income to think that is enough, even if you cannot save.
All young people, understand that time an money are linked. It is not the same to invest early than late, it is not the same to invest more early that try to invest more later. 100 is worth 100 today, but 800 in 20 years if you play it safe but well. Make no mistake, you will need to start creating your wealth.
There is nothing wrong with living a good life but only if you can afford to do that along with savings and other necessary stuff. Most people make the mistake of spending all their earnings on materialistic things to enjoy their life instead of building assets, making investments, or even increasing their savings and all these things should be the priority for someone who is earning more than what they need to spend in a month. If your monthly expenses are taking 50% or less of your total earnings, you should use the remaining 50% in the best way possible.
Most people spend their remaining funds on themselves instead of building their future and when they get older, they start regretting their decisions because now they can't work and they don't have money nor any assets that can earn them money without much work.