The third-tone piǎo is the 'bleach' sense: 漂白 (to bleach), 漂白剂 (bleach, the agent), 漂白粉 (bleaching powder). For floating use piāo, for pretty use piào.
Three-drops water on the left, indexing 漂 in the liquid family alongside 河, 海, 流. The base meaning is 'to float on water'; only by later metaphor did the pretty / glossy sense develop, picturing something that drifts gracefully on the surface.
Right side 票 supplies the sound. The same phonetic powers 飘 (to drift in the wind), 瓢 (gourd ladle), 剽 (to plunder). 票 originally pictured fire flaring upward, fitting the 'light, fluttering' flavour these characters share.
