1. Start off in the right place.
If you’re in doubt about what your listener already knows or comprehends, simply ask. As you start to explain, he suggests, ask questions like “Do you already get this?” or “Is this making any sense?”
2. Don’t go too far down the rabbit hole.
Most of us love to learn — but we can absorb only so much at a time. Avoid bombarding people with too much knowledge at once. It’s better to explain, say, three things that someone will understand … rather than barrage them with a whole load of information that kind of undoes all of your good work to begin with.
3. Go for clarity over accuracy.
It’s better to come up with a simpler explanation that maybe isn’t completely technically correct but it gets the point across. Settle for establishing a basic understanding in them. If they want to know more, you can build upon that knowledge and create a more complete — and accurate — picture.
4. Explain why you think your subject is so cool.
If you’re taking the time to explain something to someone, there’s probably a reason you’re doing it — either you think it’s super-important or very, very interesting. The more you can communicate your enthusiasm to others, the more likely they are to feel that way too. One way to do this is give examples that demonstrate how the subject is relevant to their lives can bring it to life for them.
Reference: https://ideas.ted.com