Make everything as fun as possible and any time she hesitates, be supportive and encouraging without babying her. The more you do this, the better she will be with new things.
Not all dogs like water or like to swim. My current dog loves water in every way, shape and form that he can get it, but my foster puppy prefers to wade. When I introduced my dog to water, I picked him up and took him into the water with me and set him down in it where he could still stand on the bottom and then praised him a ton. It didn't take him long to discover the joy of swimming and now goes crazy when he hears it.
Elaine and the herd