The best way to keep your flowers fresh is first to always keep the water level of the container as full as possible, ensuring all stems are submerged with fresh water at all times. It is important to change the water as often as every other day. When you change the water, cut an inch off the bottom of each stem at an angle. Be sure to keep your bouquet in a cool location in your home, away from direct sunlight or electronics and appliances that give off heat.