what can i do to take better care of my teeth ??????!

so i used to brush my teeth before schoool in the mornin and once before bed. well these past two days i decided i need to take better care of them. i already flossed regularly but now i am brushing after every meal and using listerine. i also picked up some whitening strips , how often should i use these bcuz im already using this whitenin gel with my toothpaste every night.... is there anything else i can do to keep better care of them... what will make them stronger ? any suggestions ?ALSO, i havent chewed gum in over 6 months..i DO brush my tongue lol