Float the bag for a little while to equalize temperature. Then gradually add water from the tank to the bag, giving fish time to acclimate after each addition.
When fish is ready, pour him into a net and then transfer to tank. Many fish stores have parasites or diseases in their water, and you do not want to run the risk of dumping those into your tank.
joy to the fishes in the deep blue sea
55, 30, 30, 20, 10, and 10-gal. freshwater tropical tanks