Whenever it's time to take the kids to the pool, I always reach for one item first (after I take a deep breath, of course). The item may surprise you. It's a baby sling.
It's simple, really. I started using it years ago when my elder children were babies. I wanted a way to be able to take my baby in the water with me, but I wanted a surer way to keep track of a slippery, wiggling, excited baby than just my trusty arms, especially when I had more than one child to keep track of . . . Enter the baby sling.
It answers my needs perfectly. It's lightweight. It can hold my baby arms-free if needed (though I usually keep one arm around him). It doesn't get yucky in the water, and if it does, it's much cheaper than some of my other carriers to replace. My babies have all loved it as well because they feel they have some freedom with their arms and legs to enjoy the water while still feeling secure.
All in all, it's been a great and simple tool to make pool time with a baby an enjoyable and safe experience. I highly recommend it!