Leave the flowers in their plastic sleeve and stand them in clean water for a few hours to properly hydrate.
Diagonally cut the stems.
Put a small amount of luke-warm water containing Bouvardia cut flower food the vase. Stir well to ensure that the cut flower food dissolves and then fill up the vase with water.
Make sure no leaves are left hanging in the water.
Keep the flowers out of direct sunlight and drafts.