What is the proper way to behave?
people say your head and stuff, but how do you know if you head too high or if your back supported? also, are you supposed to keep this position while you walk?
Hello, it's great that you want a good position because it very good for your heart body. Basically, he said: "There are several ways to determine if you have good posture. If you stand against a wall with the back of touch your head and your feet six inches from the baseboard, there should be a gap of two inches between the wall and the back of your neck and a slightly larger gap between the lower back and the wall. "I got this from: http://www.quality-exercise-equipment.com/tips-for-good-posture-correcting exercises.html I read the whole page and the bottom is a free guide on how to obtain a perfect posture, then hope that helps! Oh, yes, you should also keep this posture when you walk as much as possible, but do not overdo it like the first time it will be a little tiring on your body until your body adjusts him. 
Best wishes! LOL PS I just realzed that these two pages are both free guides to download! I will also check and see how they are different, but both look great. Good luck!
Walking a Hill with Correct Posture Alleviates Pain