Baptism is one of the most important dedications that a Christian can make. It allows us to be born anew - shedding the old nature and moving towards perfection in Christ Jesus our Lord and Savior.
Whether you are baptising children or adults, the same general principle applies. The person being baptised usually enters a pool, lake, river or ocean, and the person is completely submerged under water. When they come up the ceremony is complete.