You will find that some flowers in a bouquet last longer than others. Cutting one or two inches off each stem at a 45-degree angle, every few days, and changing the water at the same time will help your flower bouquet last that little bit longer. As your bouquet gets smaller with time, remove the flowers that no longer look nice and pull out any dried out or yellowing leaves. Finally, when you are left with only a few decent looking flowers, cut most of the stems off (at different heights) and arrange the heads of the flowers inside a small container (here, I used a candle holder with a glass container inside filled with water). If you look closely (click the picture to enlarge), you can see some brown and dried out bits, but I think you will agree that it still looks nice.