You can add color and contrast by adding in secondary (filler) flowers. For this wedding, I added in a hint of blue by cutting off the blooms of a delphinium.
I cut the slender lateral stem short and applied the flower adhesive.
I tuck it into place between two rose heads.
I like clustering smaller flowers, it seems more natural than a "all over design". But this is designer's choice - you put the flowers where YOU like them to be!
I tucked a few more in on the other side of the center rose heads. Be careful - it's easy to get carried away and have your final corsage grow larger and larger.