05/05/2011 at 02:00 PM EDT
It's getting down to the wire for Hugh Hefner and his fiancée Crystal Harris, who will wed
on June 18 at the Playboy Mansion.
founder, 85, announced on Tuesday that his and Harris's wedding invitations have gone out, and friends and family have already started receiving them.
"Crystal Harris and Hugh M. Hefner request the pleasure of your company at the celebration of their marriage," the invite that Hefner Tweeted
And when it came to how the invitations would look, Harris took the reins.
"Crystal pretty much designed the invitations the way that she likes it," Playboy
publicist Kellie Olisky tells PEOPLE. "She had this idea and we found this company who will help us out and they have been great. Papeterie is custom-making everything. Hef picked the paper; Crystal picked the colors."
Although the invite appears to look relatively simple, it's part of the bigger event.
"We have added little fuchsia and turquoise Swarovski crystals on the invitations, which are really pretty," Harris, 25, told PEOPLE. "And we are going to have fuchsia and turquoise flowers at the wedding, so it will all come together really nicely."
So just how many lucky folks will receive the glamorous invite?
"Well, we wanted between 250-300 people, and it's gone up to the 300 mark by now," Harris says.
As for Hefner, he has no doubts about taking his relationship with Harris to the next level.
"We really complement one another," he has told
PEOPLE about his much younger bride-to-be. "We have a wonderful time together, and I love her."