Demi Lovato, will you be our life coach? If she ever gives up her day/night job (Demi, please don't do that!), she'd make an excellent one. After all, she's written "Staying Strong," a book of inspirational quotes, and as August's Seventeen Guest Editor and cover girl, she doles out sage advice and opens up about what she's learned after checking herself into rehab in 2010. Beyond coming to the realization that confidence doesn't come from what other people think (and that includes boys), but from within, Demi shares the importance of friendship and how to overcome obstacles.

"I tell myself five things that I'm grateful for, for every negative thing that I think," Demi said, explaining her personal confidence boosters. On supporting friends' confidence, she added, "Another cool thing girls can do: You know how people have swear jars, where if you swear you have to put a dollar in a jar? You could do that with feeling insecure -- every time a friend says something bad about themselves, they have to put a dollar in a jar. [And then] you can donate it to charity."

You know how they say you can tell a lot about someone by who they choose as friends? Demi shared what she's learned about surrounding yourself with good people: "I like to have friends in my life who believe they're going places and are working towards their dreams. When you're growing and the people around you aren't, That's when you have to start shedding them. I've done that over the past few years, but it has been so worth it, because the people in my life today inspire me to keep being creative, to have fun, and to be a good person."

Demi also opened up on the difficulty of overcoming setbacks after rehab. "Since I went to treatment, there have been days when it's felt really easy, and I've felt great where I am. But then I've had moments when it's not. That's life." She added that while it's not easy, taking it day by day helps. "You can't just take your mind and your body into the shop and get it fixed. It doesn't come out repaired. It's not like a car. It takes time -- pace yourself. Every day is a new opportunity to change your life and be who you want to be."

For more of Demi's life advice, check out Seventeen's August issue, on stands on July 1. And don't miss Demi's appearance at the Logo TV Trailblazers Awards on Wednesday, 6/26. Demi embarks on her "Demi World Tour" on Sept. 6 in Baltimore.