New Rose Team Leader Skin and Warpaint coming to Fortnite with V.5.1 tomorrow (July 24th). To unlock the two new Founders Skins you need to buy a Save The World Edition (Standard or Higher). Right now Save The World on Sale, 50% off, so you can get the game including the founders skins for $20.
If you have already bought the founders edition you can check your inventory for the Founder’s Glider that unlocks after buying one of these edition. When you see it in your inventory you are good to go and will receive your new skins tomorrow.