TL;DR: Pray.

Realistically they couldn't do anything short of become a Chinese protectorate. Trump and his psychos wouldn't be constrained by the civilian-death-minimizing ROEs that the US historically uses and which have enabled guerilla warfare as a viable strategy (yes I'm being serious) so there's next to nothing that could be done in an actual hot conflict. There'll be american deaths, especially because these fuckwits will absolutely attempt something like an opposed landing because it'll look badass, but Venezuela lacks a viable path for denying the US air supremacy and once you lose that there's not much left that can be done.