Crystal Hefner's new fiance admitted keeping his proposal planning a secret was difficult

He told PEOPLE: "It runs so contrary to our connection to keep anything from her [but] there was just that small buoying force of knowing how happy the surprise would make her that made it so worthwhile.

"If you know Crystal, you know she doesn't miss a thing. She's that wonderful combination of smart and attentive, so I really had to step up my game to avoid an overshare. I also had a LOT of help from a whole host of people that did so much of the work. I definitely have them to thank for the best parts of the surprise."

Meanwhile, Crystal - who was previously married to Playboy founder Hugh Hefner - revealed the pair would love to tie the knot in the Cook Islands, where they have enjoyed some wonderful getaways together.

She said: "We love somewhere warm and familiar to us, Hawaii and the Cook Islands would be perfect options. We've had the best time in the past in the Cook Islands, so that's at the top of our list.

"We want to be close to nature, close to the ocean, and just have things be simple and beautiful."

Us Weekly previously reported that Ward popped the question at Crystal's Hawaii home with a "six-carat, vintage mine-cut diamond set on a whisper-thin band".