Most pools prefer you wear man-made fibres that don't clog up their filter systems. Any clothes must be clean and only be used for swimming, not as streetwear. A hoodie with a nylon tee shirt and long pants or jeans make a comfy outfit for your swim training. Polyester stretch jeans are made of an amazing lightweight fabric with great stretch allowing mobility and also incredible recovery. These jeans keep their shape over countless swims.
Hoodies provide a lot of drag resistance in the water. They help build strength and stamina, because they get heavy when soaked and then just feel awesome. Simply go into the water as you are, dressed in long pants or jeans, t-shirt and hoodie. No need to get changed before your swim.
Always have a hoodie and long pants in your swim bag so you're ready for an amazing fitness workout. These clothes are fun to wear in the water while you get fit. Think of it as aquatic weight training.