@RosethornRangerTTV
oh that's a good question, maybe the question in especially early stage organizing, and I don't have a single answer for it since it always depends. maybe that is the answer.
assuming you can agree on some mutually shared goal or outcome, but the way there seems impossible, figure out why that is. I think when ppl daydream they sort of implicitly imagine at least the outlines of what it would take to make real (if that's desirable, some daydreams are bad daydreams), so I always start by trying to understand what that barrier looks like for them.
more often than not it's bc they imagine themselves doing it alone, or can't picture getting other people involved. so that usually looks like convincing them they can't be the only one with the same dream, identifying potential existing groups to work with, or helping through an initial phase of putting ppl in contact.
there's a tactic in union organizing (and I'm sure elsewhere) of "snowballing little wins." say you want to organize a union in your workplace. you could just 0 to 100 try and Start It and call an election ASAP if your coworkers are already aligned and ready, if that works you're extremely lucky. you could also start smaller, get a few coworkers together, advocate as a group for some shared interest like idk a coffee machine in the break room or whatever. that feels good to the ppl involved and demonstrates the power of what we can do together - the smallness of the win is the point, if we can do this thing with hopefully minor effort, what could we do if we were more organized? roll that group onto another win, picking up whoever you can, and so on.
So I also try that a lot, eg. by making some minimal version of something as an example, or pulling off a small action or event to build trust among a group. that's something I have been less good at lately bc depressed, but showing someone something is indeed very possible because look at that we just did a little piece of it is very different than just persuading them.
related but still complementary to the much more general tactic of breaking the problem into smaller pieces - what's impossible about that? ok so what if we did something first that made that impossible thing less of a problem, repeat. what's the minimum step we can take in that direction?
on the other side of lowering barriers to action is raising the perceived stakes of inaction. eg. bring it up slowly, gently, but repeatedly, demonstrating how the lack of that thing impacts their life in potentially unexpected ways. IT is too slow. maybe it wouldn't be if you had shared governance. the university decided to turn off the AC in our building. maybe they wouldn't if you had shared governance, etc. This is delicate because you don't want to harangue people, but do it in such a way where you're on their side (hopefully you are!) - "yes that is bullshit, and I know you have your doubts but this is one of the reasons I was talking about xyz." people like empathy and being able to vent about stuff. people do not like know-it-alls that don't shut up about stuff. (I can be bad at this when I'm not actively trying to organize ppl but just passively venting, and friends will remind me I'm not being helpful to my own cause, which is true lmao).
context is extremely important but also intangible and difficult to define. I usually try and establish a context that something might happen in, so rather than some abstract idea that we can do, it has a name, a space, etc. that concretizes things and helps feeling like you've already started. You also have to know when people have soured on a context - even if they still share the same goal, they don't believe x group can do it or y has shifted direction. you yourself can also be the context, so sometimes you need to take a step back and let them cook on things on their own for awhile. it's sometimes hard to know when you've reached the point where you should cut your losses and start over, refresh context, but I think it often comes sooner than ppl are willing to admit - maintenance is noble and you should try and make things work when you can, but letting a group break up and reform, even if it's a lot of the same ppl, can be healthier than trying to get it working again where eg. some people might no longer feel welcome, the sense of futility has taken over, etc.
anyway that's just a couple tactics out of like infinitely many of them. I would never call myself an expert on the topic, other ppl more seasoned than I probably have better ideas, and if I had active haters they could probably point to a dozen times I have failed or fucked these up.
I spend most of my time planting seeds in the hopes that other ppl run with them bc I can't possibly tend to all of them, so u have to know that balance too - when should you commit to driving something ahead yourself (with others, hopefully), and when are you casting seeds hoping some of them sprout. often the best way to get ppl to do something you think would be a good idea is to help them believe it's their idea, and usually it is anyway, at least in part, they just need a little push. none of this should feel manipulative, we're helping each other to feel powerful, not tricking each other 
some tags for my own reference since this and related topics come up a lot for me:
#organizing #seeding #PlantingSeeds