Caffeine pills are cheap as shit their over the counter in most supermarkets
Have around 200-400mg or untill ur hands vibrate hardcore
Ur better off with a phat banana and strawerrys anyway (sounds homo but is a sick cheap easy preworkout)
Those are the caffeine pills I have for pre workout here and there. 1-2 pills (200-400mg) seems to get me going real well... and keep in mind almost no preworkout supplement does much for me >.>