I don't have good tips for mind-reading in particular, but if you have a decent sense of how much the typical person already understands, these sub-skills I picked up in college should be able to help you, almost certainly not an exhaustive list:

• Baby Steps - it's tempting to try to shoot straight for the thing you care about explaining. But if you try to describe it directly, even using very simple terms, you will be moving too fast even if the other person technically knows enough to eventually unpack what you're saying. If you do this your sentences will rot before they can be digested. Instead, spend at least a full sentence or two on each individual step from common knowledge toward your destination.

• Stopping - this one is really hard, but after you've made each point, actually pause for a few seconds and look at the other person's facial expression and body language. Very few people are trained to explicitly ask with words, "can you unpack that a little?", but they will often say it with their face. This also gives them the chance to ask specific questions, or to process what you just said before you move onto the next thing. You can also ask explicitly whether you're being clear; wait for an answer before moving on.

• One step forward, two steps back - be ready at any point to move back more than one step if it becomes evident that something hasn't been understood. If you really weren't understood the first time, then it's as if you didn't say it. If you find a different way to say it, it won't sound like you're repeating yourself; it will just sound like you're being clear.

• Laconicism - if there is a detail that is not important, omit it. It doesn't matter if this means you're saying something that isn't strictly in every detail literally categorically true. (I still have trouble with this one.) All that matters is you move the other person as far as you can toward a true belief. Don't volunteer unimportant details unless they ask. (If they ask, then (a) telling the truth is the right thing to do, and (b) that means they understand the basics well enough to ask the question, which probably means they can handle the complicating detail.) There will always be aspects to a topic that interest you, and may well be important, that you should omit from a beginner's account.

Wow, how did I miss this? This topic is one of big interest to me, since I seem to be much better at explaining things to others than getting a sufficient explanation out of others. It's a routine occurence for me to train people up to my level in a fraction of the time it took me to get to that level.

I strongly endorse fiddlemath's post, as it basically matches my approach, and I appreciate the link too. Thanks to jsalvati for mentioning my latest remarks on the matter.

So, here's my general strategy:

First, you have to want to explain it. (This doesn't seem like a problem in your case, but it's important in general.) It's tempting to maintain one's monopoly on knowledge and get divided between pursuing that, vs. actually trying to convey an understanding

Second, you need to have a deep understanding yourself. In this context, that means a Level 2 understanding, which means you can not only come up with the right answers in a domain, but have a model for that domain that deeply connects to other domains so that you can see how they're related, and what each implies for the other.

Third, you have to find the nearest point of common understanding ("nepocu"), which identifies the extent of your inferential distance. So, your filter questions should be aimed at identifying what common understanding you can draw from, so that you can take what you both know, and guide the listener stepwise to the parts that only you know. Build up every pre-requisite concept (sometimes several layers out), starting from this nepocu.

With all that in mind, here are some guidelines to follow, using a recent non-interactive explanation for examples:

Always be ready to "fall back a level" and explain the grounding concepts and prerequisites for what you're currently having trouble with. This is where the Level 2 understanding comes in: if your model for this domain is well-connected to your model for the rest of reality, there are arbitrarily many "inferential paths" you can take, and so you're always able to start from a domain closer to what the listener is already familiar with.

Note: for many people, the very idea that the body of human knowledge is mutually connected ("consilient") is novel, and their experience with the education system may have steered them away from even thinking like that, so they're used to looking at any topic as a bunch of random facts to remember. Connecting different areas will make things really "click".

Motivate each step in your explanation. An explanation is easier to follow if the listener knows why you're explaining it, and therefore what important things to look for. (This is why, in the linked blog post, I first explained what a signature must accomplish, before I describe the mechanics of public key signatures.) When explaining a process or method, it's confusing for someone to hear all the numerous steps, so it helps to start with, say, a naive, straightforward (but wrong) method and say something like, "But if you do it that way, it has this problem, so we do this instead" ... and gradually build up to the full thing.

Recall what it was like before you understood the topic and imagine what sort of things you wish someone would have told you. If something seems counterintuitive to a newcomer, acknowledge it from the beginning so they're not stuck wondering about it.

Hope that helps.

(An article I've been writing on this has been in development hell for a while now...)

I was a TA for a while and was taught to use Socratic methods. If people have some background knoweldge, you can get very far by asking people "what would happen in this situation? what about this situation? Now if you apply this situation back to this one, what happens?" It depends how much time you have, but lots of questioning interspersed with some explanations seemed to help most students the best.

If you are trying to teach someone, I think doing that is better than telling, because then when someone else has made the inferences it will become more a part of them and they will remember more. However, doing this repeatedly is also good for learning to explain, because you learn all the different things that people get hung up on---what inferential steps are most difficult to make.

Note that if you want to be really good, you'll have to do a LOT. After a year of 4 hours a week of face-to-face TAing, I was finally able to help people through most types of problems and had reached the 'competent/actually helpful to most people' stage.

Explaining things is also something where there are many paths to the same goal. Different explanations will work for different people. To be the best explainer, you'll have to learn many different explanations. Read many viewpoints on transhumanism by different people and as you read them, try to think of how you would explain it to someone else. Build up a repertoire.

Try to taboo all the relevant vocabulary so that you are forced to think about what the words and concepts mean in more precise language.

Like many problems in self improvement I think this comes down to a two essential factors, Practice and Evaluation. Social activities like convincing people need extensive real world practice to effectively apply, even with the best advice. However, improvement can only be made if you know how effective you are actions are.

that much is obvious

As an initial suggestion: locate only groups on difficult but none controversial topics and practice convincing people of things, asking them to rate their knowledge, opinions and beliefs before and after

perhaps we could set up such a thing here on less wrong for people to practice on one another or does that seem to Dark arts to people?

By "explain" do you mean "communicate" or "persuade"?

Everyone has seen cyborgs, androids, avatars and virtuality in the movies. That aspect of transhumanism has been communicated, as a set of possibilities. If you want to persuade people that they might want to commit tof that sort of thing themselves, then you have to understand them. Value-shifts always start with the values someone already actually has.