Unlike most cut flowers, tulips keep growing in the vase. Place the wrapped bunch upright in a container holding cool water deep enough to submerge the exposed stems. Leave in a cool place for an hour or two. Now return them to the vase. Most bulb flowers like cut flower food in the water.
Tulips are the exception.
Fresh tulips will last a good week or more in the vase with some help. For longest flower life, keep the tulips in a cool spot in the room. You can create a wild riot of color or try more subtle single color combos such as purple with lavender, light yellow with deeper yellow. Flamed or multi-colored tulips look great mixed with solid color tulips in coordinated shades. This step allows the slimy sap in the narcissi stems to run off.