A florist needs to make money and in order for them to this they need to spike up cost tremendously. What you are paying for is not only the flowers but you are paying for the cost of the flowers, vases and containers (which they buy wholesale and mark up 50% to 75%), the salaries of the people making the arrangements, paying for the driver and gas and other incidentals. This is their business and they need to do this in order to be successful.
But if you are somewhat artistic and want to save some money, you can do your own flowers. Here are some basic things you need to do:
1) Look through bridal magazines or online to get an idea of what kind of arrangements you are interested in. Having pictures of what you like can help you decide the colors and styles. Investing in a flower arranging book can be of enormous value to you as it gives you the complete how too and what tools you need and lots and lots of pictures.
2) Without having experience in floral design, simple may be a better choice but that does not mean its less effective. Something like a tall vase with white gladiolas in them placed on each table looks incredible and is about the easiest arrangement you can put together. This also works very well as altar pieces. If you want a low arrangement you can do something like a low vase with just roses of your color choice and sprinkle rose petals around it on each table. If roses are too expensive you can do the same with cheaper flowers such as carnations, daisies, Gerber daisies or mums. Whatever you like that fits your budget.
3) Do the table arrangements and altar pieces before tackling the bridal and bridesmaid bouquets. These also typically take the most time to do. There are two ways you can go. You can go to a craft store and buy ready made floral foam with a handle and lace skirt that you will soak with water to insert your flowers into or you put freshly cut stems together and bind them with floral tape and then ribbon.
4) A simple but beautiful bouquet can be made by taking roses that have been cleaned of most of their leaves and thorns. In one hand hold the first few roses and keep adding a rose one at a time until you have the desired amount of roses. Make sure they are not all flat at the top. You want your bouquet to be rounded. You do this by carefully taking the outer roses and pulling them down gently all around until you have the desired effect. The center of your roses will be the highest roses while the rest of the roses will gently slope downward.
5) When you have decided what you want then gather up your bridesmaids or whom ever you think could best help you and well before the wedding, do a test run and make one of each arrangement you would like to do. This will give you an idea of how it is going to look and how long it takes to do each one. Take a close up picture of each arrangement once you are satisfied. Doing a run through also lets you determine the cost. Just multiply by the number of arrangements you need to do. If you are happy about your work and you really want to know what your savings will be, then take your pictures to a flower shop and get them to give an estimate for making the same arrangements. You will know what you paid, now compare that to the florists quote.
Doing your own flowers will take more of your time but if you have a good support system helping you, (which can be a really fun time) you can take pride in your accomplishments and save a lot of money.