Keep it simple, keep it imaginative and always keep it sophisticated. Very much like these flowers by Christian Tortu.
When in doubt, opt for one colour and one flower type and do it in abundance. Sixty pure white tulips make a fantastic bouquet and will always impress. This is a particularly successful formula when certain flowers are in season and are very affordable; tulips in March, lilacs in May, peonies in June, hydrangeas in July and dahlias in August.
If the choice is between a $15.00 bunch of inferior flowers or one exquisite bloom that costs $10.00 - go for the latter. The experience will be much more satisfying and luxurious.
Flowers are about the moment. They are not about four days from now. It's all about the moment you received them, the moment you impulsively bought them, the moment you gave them to someone special.
And remember that flowers are your calling card. They say so much about you and your style.