What I would have said, if I were there:

Today, I had an impromptu trip to Logan, and therefore missed New Beginnings with my young women. I was supposed to tell them a little about Personal Progress, and since I didn't get the opportunity there, I'll quickly do it here (any non-Mormons out there, forgive me).
I had two main points, and they were -
One: It's not as hard as you think.
And two: It can change your life.
Expanding on the first, let's put it this way: You don't have to add new things to your plate when you're already doing something that counts. There may be a lot of things you overlook, because you think what you're doing doesn't quite fit. But believe it or not, there's almost always a place for it. Think about what you're doing - in school, sports/hobbies, work, at home, and - basically - everywhere. What you find may surprise you.
As for the second point, don't be critical. It really is an amazing program. It gives you practice at setting goals, and the satisfaction you feel when you accomplish them.
Many of those goals help you gain habits that will help you forever - whether they be reading scriptures,  praying, journaling (which is huge to me, as most of you know), being kind to others, or serving the world around you. When I went through the program and completed my Honor Bee, I truly fell in love with service. Bringing a smile to someone's face is one of the best ways to help your life.
Here's a piece of advice from yours truly: when you start, go through and find those goals that take the longest, so you can get started on them as soon as possible. Of course, the Book of Mormon would be the biggest, but it's also the one you'll want to repeat for the rest of your life.
The last thing to mention is that once you start, you need to follow through. For most of the goals, there are four steps: read the scriptures, complete the task, write in your journal, and have a parent/leader sign it off. It's that easy.
Good luck, and God bless. :)