How do you max your cognitive abilities, /sci/?

I notice I'm becoming dumberer as time goes on. I'm working a low IQ chem industry job now, and stress, lack of sleep and pressure is causing me to experience decreased problem solving and speed of mind to a noticable degree.
I actually feel like I'm one of the dumber people walking around at my job lately, which causes more stress. There's also frequent emergency situations and I notice that I'm less equipped to deal with them. I can think on my feet to a lesser degree and sometimes my mind just goes blank.

>get sleep and reduce stress loser
I take sleeping aids but don't want to take them too often, I meditate and it helps to some degree but only for a little while.