get a good nights sleep beforehand.. be hydrated, but don't drink too much. if you decide to eat only eat something easy to digest and don't eat right beforehand.
stims do not help your workouts, just a heavily marketed thing that is cheap, legal, and addicting. the more you use them the more you will need them. just like any animal on earth we have a fight or flight response during exercise that actually becomes suppressed when you use stimulants. plus stims raise your heart rate so you can't workout as hard as you want without hitting your max heart rate, this is not a good thing at all.
so if you want to take 2 things pre workout this is what i recommend
1. n2generate 5 caps 2 hours before. it will make you more aggressive or n2kts
2. cardarine or sr9009 (hit me for codes)