If Beach vacations are for fun, Pool parties are for chic fun, if that is even a word. For me, Pool parties are to up the sundowner game
As you read in Coverups for Swimwear, there is a number of types of cover-ups like Shirt dresses, Kaftans, Sarongs, that you can choose from.
For a pool party, choose a coverup that looks good on you. You might enter the pool for some time and the rest of the evening is about dinner and drinks by the pool. Choose your accessories with a bling for the evening.