Arranging flowers by yourself sounds like a very daunting job, especially for those who have no idea of doing it. There are many simple bouquet styles that are easy to make and still look wonderful when made by an amateur. However, one still needs to dive in the area of flower arrangement to get a glimpse of what may come.
Flip through some books on simple flower arranging or check out flower arranging tips on the web and practice before the big day. These can give ideal tips to first time florists-wannabe, just for the wedding, at least.
If you decide to arrange the wedding flowers yourself, be sure to choose long-lasting flowers to allow time to finish the centerpieces several days in advance. A good example of this is calla lilies. You can also ask for help to friends, especially those who have green thumbs.
Following this route can further reduce costs by buying your flowers in bulk from a wholesale flower supplier. They will usually sell to the public at a fraction of the cost of retail flowers. Aside from the fact that you might have discovered a new talent!