Lauren Conrad a bridesmaid not yet a bride!

Preparing for her own "I Do's"! Lauren Conrad spent her weekend serving as a bridesmaid in the wedding of longtime friend Maura McManus. On Saturday, Aug. 16, the fashion designer, 28, posted several Instagram shots from the Ojai, Calif. service and reception, which used the hashtag "#oehmsweetoehm."

Bestselling author Conrad wore a cream, floor-length bridesmaid gown and wore her blonde locks down with large waves.

Lo Bosworth (left) and Lauren Conrad celebrated their friend Maura McManus' wedding on Aug. 16.
Credit: Courtesy Lauren Conrad

Her fiance William Tell also attended the festivities (she Instagrammed his name card), but the weekend was mostly about spending time with old friends. The former reality star posed in several photos with Laguna Beach and Hills costar Lo Bosworth and childhood pal Jilly Hendrix, who were also bridesmaids.

Laguna Beach friends and costars Stephen Colletti and Dieter Schmitz reunited for a friend's wedding on Aug. 16.
Credit: Courtesy Dieter Schmitz

The California native's former flame Stephen Colletti also attended the wedding, posing for a photo with his pal Dieter Schmitz via Instagram.
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"With @stephencolletti for one of the besets in the wettest @mauramcmanus wedding," Schmitz captioned the photo. ?