I've had the opportunity to work several hours a week with a sweet older couple in their nineties. They were high school sweethearts, he is a World War 2 veteran, they had 7 children, and were missionaries in two countries. While getting to spend time with them, I've learned a few things about their life that applies to someone of any age.
First, growing old is a choice. Old is an equivalent to giving up. If you ever visit a nursing home or assisted living facility; look around at the different people. There will be the one lady who goes to all the "events" and talks to everyone, and then there will be someone else sitting in a corner. The lady bouncing around the middle of the room could be 20 years older, but will still seem much younger. Some people give up, some people just keep on living. A body wears out naturally, but a soul will only wear out by choice.
Second, no one ever really figures it out. I work along side a 94 year old woman, and she still doesn't know what to cook for dinner. She still dreads some chores and still asks me for recipes and advice. That was so strange to me; her asking me for advice with little things, like if I knew whether fruit would last longer if she covered it or not. But I also realized: we never get to an age where we have life figured out. It's okay to not have a perfect schedule, or to never get around to doing everything the internet says you have to do. It's life, and it is imperfect. Don't let that fact keep you from living it.
Third, people don't change with age. It comes as kind of a disappointment to me, I'm afraid. You know that annoying-boy-thing your little brother does? That those teenage boys you know do? That your dad also occasionally does? Well, guess what? A 95 year old man does it too. It works the other way around, of course. We, as girls, never stop trying to fix guys.
As young people we tend to view old people as, well, old. Like, in our minds, they just kind of sit there. They walk really slowly, don't hear well, and just seem pretty disconnected from the rest of society. But, actually, they don't change a bit. If you get to know them, they still crack jokes like parents, flirt like teenagers, and tease like little kids. They are actually pretty awesome: the wisdom of long life with the goofiness of someone who doesn't care what people think anymore.
Forth, don't sweat the small stuff. Even "big" things now will be small memories way in the past soon. Failing a test, knocking out a tail-light in your dad's truck, saying that really embarrassing thing in front of your crush; these all may seem like game-changing mess-ups that make you want to curl in a ball and die. But don't give up. No matter what big; it will move into the past if you let it. Now, there is a difference between stupidity and a mistake. This isn't an excuse to live like nothing matters; more to live with the intention to make the right things matter and to let the little things go.
And finally, a lifetime is not that long. My dad would always say things like, "Don't blink," and "I was 8 years old, and then the next thing I knew I was 35." As a kid I never understood that, like, how on earth could time pass that quickly. But it seems like just a couple months ago I was 7, and now a whole decade has passed. The lady I work for has an amazing memory and she has so many stories; of saving her money to buy a cake pan as a gift for her mother, of going on road trips in a Ford Model T, of first meeting her husband and her uncle teasing them about each other, of surviving months waiting for him to return from war, of learning Spanish and living in Mexico and South America, of keeping toys around for great-grandchildren. Just think of how many million, billion, trillion lives have been lived on this planet. How many tears, and laughs, and wars, and loves, and memories. It goes so fast, friends. Live every day for all it is worth, because it will be gone before you know it.