The type of bouquet you choose is really a matter of personal preference -- the flowers should complement your wedding style rather than your gown. Brides in opulent ball gowns often opt for a small bunch of calla lilies and brides in silk sheaths sometimes carry cascades of orchids. It all depends on the overall look you're going for, and should reflect your individual style and sensibility.
When planning your wedding flowers, the key to getting a co-ordinated look is to either match or to contrast the flowers, against the color of your bridesmaids dresses. Matching a dress can be achieved using analogous or monochromatic colors, while contrasting can be achieved with complimentary colors. See our section Choosing Wedding Colors to see different color wheels that highlight analogous and complimentary colors as well as color temperatures.