Don’t make payments on something if you can save and just flat out buy it. When I was your age I used a rent to own place for my furniture and ended up paying 3x what it was worth. If I had lost my job at that age, I had not much in savings, so it would have prevented me from paying and I would have had my furniture taken away and a hit on my credit. 

Don’t apply for a lot of things that require a hard hit on your credit. Multiple inquiries can have a negative impact on your score. 

Don’t default on anything. Ever.