1. A collar is only needed when using a bouquet holder.
In order to build a bouquet, you'll need to know these basics. A bouquet holder is made with a plastic handle and a cage filled with floral foam. A collar is located on the underside portion of your bouquet, meant to disguise the bouquet holder.
If you are designing a bouquet without a bouquet holder, a collar can be used, but isn't necessary.
In case you're curious, floral foam is a Styrofoam (if using artificial or dried flowers in the bouquet) or a wet foam (if using fresh flowers in the bouquet).
2. Try matching your dress to your bouquet collar.
If you have chiffon, organza or tulle material on your dress, consider using the same kind of material as ribbon loops under your bouquet, creating a collar.
Using a sheer or fine ribbon will give you a more delicate look.
Using a satin ribbon will give you a more luxurious look.
Be cautious of heavier ribbons sagging as time goes by- gravity isn't a heavy ribbon's friend.
3. Foliage makes a great collar.
You can build a bouquet that functions as its own collar! You could do a variety of mixed greens or your favorite foliage. Try folding over a wide leaf to give a loop of foliage under the bouquet. Aspidistra leaves work well for creating foliage collars.