Select the floral materials. Choose flowers in color that are complementary to one another, or use a monochromatic color scheme of several different varieties of flowers in varying shades of the same color. The most interesting arrangements are composed of flowers of different sizes. Include large, medium and small blooms.
Add some filler greenery. Ferns, herbs, asparagus tops or even interesting leafy stems of shrubs or perennials not currently in bloom all make good filler greens.
Choose a container. Short-stemmed flowers look best in smaller, rotund vases, while long stemmed flowers look best in tall vases that are slim in proportion to their height.
Remove all of the leaves from the flower stems below the water line. Trim off about an inch from the ends of the stems.
Place the flowers in a bucket of room-temperature water for about an hour to re-hydrate and freshen them.
Fill the bottom third of the vase with clear marbles or floral support stones. The stones will help hold the stems steady so they stay where you arrange them.
Begin with the largest flowers. Insert one in the center of the vase so it creates the topmost point of the arrangement. Add the rest of the same variety of flowers to form the outside points of the arrangement. Cut the stems, if necessary, so they are the right length to fit in within the arrangement.
Add the next largest variety of flowers. Fill in and surround the larger flowers with medium-sized blooms, cutting the stems for correct placement of the blooms within the arrangement.
Fill in the area around the flowers with greenery. Create a frame for the large and medium-size blooms, creating a shape that is at least twice as wide as the vase or container is.
Add the smallest blooms as accents, putting them among the greenery as small accents.