Leisurely swimming, such as at a beach, in a lake, or in a pool, implies good fortune and easy living ahead, unless the weather is bad, in which case danger could result from doing the wrong thing at the wrong place at the wrong time.
Swimming toward the shore indicates getting to where you want to go, but only with a lot of hard work. How difficult that will be depends on the circumstances (especially the weather) and the other symbols in the dream.
Swimming for your life in a storm warns of great difficulties ahead.
If you reach the shore, or if there is a star or lighthouse guiding your way, you will prevail.
Swimming in a meet implies an inner drive to improve yourself.