How do you know how much of what to get?

I have been able to judge what I may need because they tried me on a plethora of drugs back in 2014 - risperidone, abilify, chlozopine and id been on Zyprexa in the past. i was on 50mg of Zyprexa at one point so i have a good tolerance.
i know many people who ive befriended from the psyche ward and from them i get their stories . I knew sum1 on lithium and i looked up the therapeutic dose and tried it. then i read that abillify helps mood and i remember being on it and my mood was ok but my concentration and thoughts not right. i know the internet isn't a reliable place to find medical information. I start with a low dose and add to it gradually.
Ordinary mood drugs like mirtazapine and venlafaxine just aren't cutting it, i still take them but i have schizoaffective and anti psychotics that are potent are the only ones that work on me. abilify is often an add on even with another anti psychotic. i also realise that mixing is an issue, when experimenting.lithium was only drug i tried on my own that i hadn't been issued in hospital and it worked but it f**ks the liver so ive opted for abilify.

Seroquel is my main medication for sleep, concentration, racing thoughts. Abilify does not have the same sedating qualities but helps mood.

But i have blood tests, an ecg and others in over a weeks time, i think they will be miffed to find other drugs in my system. I will just plead ignorance as i cant afford to stop taking any . Got important assignments to do.

I know I'm playing with fire, and i realise the risk with taking new drugs, but i can't live with my natural state end of story. Its a calculated risk at the end of the day, i do my research draw on past experience.