What is the golden rule need to follow while using BA?

everytime before using the BA make sure the oxygen content is enough by looking at pressure gauge and make test if supply of air good, make check the face mask for any leakage and make sure the BA fit in your face with all strap on. make sure the whistle is working if ever the bottle is going to run out of oxygen. during use make sure that you downed the BA properly, dont full open the valve, open only which is enough for your flexis, check pressure gauge make sure it is full, clean the visor glass, check all strap pull equally to prevent leakage of air, breath moderately, relax so that you can conserve your energy and the way you breath will be minimize. after use remove the empty bottle and replace it with new one and refill the one that been remove put in a bucket with cooled or warm water so that during filling time the bottle will not explode the water as agent use to control.