To mirror @Ithorian@hexbear.net, rage, continuous varied education (both self and institutional), weed, and the fact that when I talk to people they usually agree with me, even if it doesn't always stick for them or proceed towards a greater understanding and comprehension of the material world for them.
The incoherence of the average American's politics chiefly lies in the fact that the inescapable propaganda (it literally starts from before school) around them constantly lies and obfuscates reality, something that cannot be avoided, as even if you personally do not watch it, that would also mean cutting out every person in your life that is susceptible to propaganda who then repeats it as if it is fact.
Specifically the incoherence comes from that fact that despite this bedrock and ocean of propaganda we live in, lived reality cannot help but assert itself for the majority of people, and the contradictions between what we are told we will experience v.s. what we experience and how we are told to process those experiences v.s. how we actually process those experiences are quite large. However, because most people do not have any experience or knowledge of critical theory, for them there is no formalized way of making sense of those contradictions, leading to an incoherence and contradictions within their own grab-bag explanations. Ultimately what this means that you can cut through it, but it is incredibly difficult to make it stick. They have to be interested in doing it themselves. My usual social goal is to encourage that formalized exploration.
I mostly point out material contradictions, discuss the idea of class analysis, discuss history generally, and talk about dialectical thinking. I usually let their interests direct the conversation.
Edit: Also, people are receptive to Marxist thought, just don't immediately pit them against their boss, especially if they work in tech or at bars. It's gotta be more esoteric, like in terms of financial crap.