I'm of the belief that if you have some understanding come up, and even if you forget it in the next 10 minutes, its going to be in there somewhere, it'll come up again. I'm not too worried about "holding on" to understandings or insights.
There are some people who have what they think is some sort of insight in their meditation and they want to write it down; they want to hold onto it; they look at it later; they try to remember it. I don't agree with that sort of practice, in the sense that they're trying to hold on to something in the past, which then often blocks them from growing. I'm of the belief that if you've developed some understanding, even if you forget it in the next few minutes, it'll be in there.
Look at it this way. Probably all of us rode bikes as kids, and when you get to be an adult, usually you don't get to ride a bike so often. Some people do of course, but there are many people, like myself for example, from about the ages of 22 to 29, I didn't ride a bike. When I did ride a bike again, it was like, "Mmm, Okay, I have to relearn riding a bike". Because bicycles, of course, are slightly dangerous, you can fall down. So, the first time I got on I didn't feel comfortable, I didn't feel that confident. It also happened to be an 18-speed and I'd never had anything except a 3-speed, so I was nervous getting on the bike, but I rode bikes for years as a kid. After I got on, after 5 or so minutes, I was then comfortable again. The memory came back, the understanding came back, but I didn't have that understanding fresh, when I got on to that bike. It was 8 years from that understanding; it was kind of "lost". So, to a certain extent, whatever you truly understand, it's going to be in there. It'll come up again at some later time, hopefully, if you are continuing to grow.
Now on a different angle, some people will write down their insights and understandings, but then okay, as the question goes: "How can you move from just understanding, to application of it in our life?"
For those of you who are keen on that angle, write down your insight, then write down the Ten Paramis, and write down how that insight could work in all Ten Paramis. Do it as an intellectual exercise, which might then stimulate you to apply it in your normal life. You might see a clear way that that understanding might go right into effect. If that suits your nature, fine.