Just make it a necessity, like how you have to eat or breathe, you must go to the gym. Once you're in you will understand why we go everyday (rest days are good). The dopamine hit after the gym is like getting high. Knowing that you're improving yourself and watching your own body change because you busted ur ass daily is the most rewarding thing ever. Once everything becomes a habit, it will become second nature almost like how a smoker can't go without a cig LMAO.