Matt Jones/Cosmopolitan

Lauren Conrad has come a long way from her debut on the reality television teen drama "Laguna Beach." The now 27-year-old fashion designer is all grown up and newly engaged in to rocker-turned-law student William Tell.

Conrad appears on the cover of Cosmopolitan's January 2014 issue and in a candid interview, the blonde beauty dished on her new engagement.

"I had no idea it was coming," Conrad said of Tell's decision to pop the question. "I thought he would wait until he finished law school."

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According to Conrad, the former "Something Corporate" vocalist planned the surprise proposal alone, even choosing a traditional 2-carat diamond ring on his own.

"He didn't even ask my friends, which was a bold move," she revealed. "He said, 'I know you, and I know what you like.' And I love it. It's perfect."

While Conrad is admittedly smitten with her new fiancé, she discouraged readers looking to follow in her footsteps from rushing to the altar.

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You have the rest of your life to be married. Enjoy falling in love," she advised. "When girls get caught up in the timeline, it becomes more about the wedding than the marriage. You should be with someone with whom you could elope this weekend and be happy."

"William hates it when I say this, but he really is a very nice guy, and when you meet a nice guy who also manages to keep your interest, that is the dream," she added. "If you're going to settle down, it should be with someone you can't stop thinking about. Especially if you're in your 20s. If I were single in my 60s, I would totally settle. I would!"