I’m not used Melon Mambo and Old Olive. The card base is actually Shimmery White as I find it a little more substantial than Whisper White for supporting the weight of the whole card. The little suspended hearts are made with the Heart to Heart punch
DIY: have every person that comes to your friends party attach a candle to their card; any candle (that fits on the cake) will do. Then, as your friend collects the candle and puts them on the cake, it creates a wonderfully random collage of candles!