The former The Hills reality star went for a dark and sultry look for the cover, paired with big, wavy hair.
"Take any trend you want and relax it. That's how California does it," Conrad says of her beach babe style. "If it's silk button-up shirts that are in, you probably don't button them all the way, and you cuff a sleeve, you know what I mean? It's almost like how your outfit looks at the end of the day."
Conrad has kept busy since she left The Hills in 2009. She released her fashion guide, Lauren Conrad Style, in 2010, and her sixth novel was published in 2013. In addition, Conrad has launched several of her own fashion lines, including the upscale Paper Crown.
"Your bed is for sleep and sex," Conrad says her busy schedule and habit of working in bed. The author and designer also has a wedding to plan, as she and former Something Corporate guitarist William Tell became engaged in October 2013.
The two moved in together a month before they got engaged, and Conrad says that she has had to tone down her feminine decor.
"If it was up to me, my home would just be over-the-top girlie and vintage, but I share my home with a gentleman now," the star jokes.
The April issue of Allure will hit newsstands March 31.
2014: The Year in Music [PHOTOS]