Your endeavor is good. To go there, I recommend some preparation steps.
- define what you want, in as much detail as possible, not SMART;
- understand what you miss in order to be there, where you want to be;
- ask the people around you (family, colleagues) about how you can improve your explanations; what helps them get into the subject better;
- remember Einstein's quote:
"If you can't explain it simply, you don't understand it well enough."
When you "advanced" enough clarifying the above topics, you will have enough information about how to make hings "measurable".
Please be aware that sometimes "measurable" cannot be realistically measured in real life.
Example: I had one colleague. Natively, he used to talk louder than very loud, regardless of the situation and unrelated to the message being transmitted. Colleagues started to train him to talk less loud. Partially they succeeded, and then I lost contact with those colleagues, I do not know the situation right now any more. Question: how can that colleague make his target measurable, that he should talk not so loud? Carry a decibel-meter with him ll the time?
My conclusion: keep improving, but do not over do it when it is not needed. Doing S.M.A.R.T. things is very good, but doing REASONABLE things is also good.
From my experience: I find that it is quite helpful to use metaphors and comparisons. If I try to explain to my mother something about the computer in computer terms, I lost her. But I know she knows things about clothes making. So when I explain I go something like:
This thing about computers is like that thing about making clothes.
or:
There are many kinds of programmers. They cannot do each others work successfully. Like the two tailors: one making underpants, the other one making winter jackets. They will not be very successful doing one another's jobs.
I also find it very helpful to draw sketches of the explanation. As I go ahead explaining, I keep drawing - as an example to the explanation. In this way, the other person does not need to memorize all the explanation, and does not need to have a strong ability to imagine what I explain. Everything needed is right there in front of their eyes.