So before the 31-year-old departed for Paris to celebrate with her long time pal, we caught up with her to get her thoughts on the biggest wedding of the year.
"I can't wait to get there and spend time with her so we can check out some of the museums and lunch at all the little cafés," she gushed.
As for the main event itself, Brittny already has her outfit picked out. " I have decided on a beautiful Michael Costello gown that is so over-the-top glam—just how I like it."
Not that she's going to upstage the bride. "I know Kim will look glowing and dreamy because this is such a special day for the couple and North." Gastineau also has a few ideas about Kim's bridal beauty look: "Being Kim is a glam gal I think her dress and hair will complement one another."
To hear more about bridal beauty trends from the Eye On Glam lifestyle blogger, watch the video below.
Don't miss Keeping Up With the Kardashians Sunday, June 8, at 9 p.m. on E!