I’ve seen in the top runs that there are people doing different heist preps at the same time, how does this work and how do I do this on PS4? Me and some of my friends are trying to go for some quick times

How hard can it be to think of a descriptive thread title, fucking hell.

The same way you've probably seen in mentioned top runs. Multiple CEOs. One being the main host, and other(s) CEO(s) can start different preps and bring the item to the main CEO for him to steal and deliver inbetween other preps.