If there is something you want to do in life, get it done sooner rather than later. Later may not be there. Actually, later will, but you may not, or your circumstances may make your goal, once possible, now impossible.
In life, you will have a few friends, a few enemies, and a lot of people who don't matter either way.
Don't make unnecessary enemies.
Everyone has certain good points and certain bad ones. Learn what yours are early on.
Buy the best and cry once, whenever it makes sense.
Don't learn the tricks of the trade. Learn the trade.
There is schooling, and there is education. The two have little to do with each other.