Always Plan. You may postpone your flower shopping until the last day before your wedding but it is always wise to plan ahead, as you may end up spending more than you expected doing the last_minute purchase. Moreover, planning ahead for your wedding flowers also gives you enough time to purchase the flowers that you want to have at your wedding rather than picking the available ones.
Next, fill your "real" vase about two_thirds of the way with warm water. Make sure it doesn't leak. Add flower food if available. (Follow the instructions on the packet.) Place a few of your larger blossom flowers in the vase and step back. This will give you a better idea of how to proportion your bouquet. If the stems are too long, simply cut them shorter. If they are too short, try a different container, or add pebbles or marbles to the bottom of the vase to elevate your flowers.