If you love flowers on your cake, but don't want to try to create them from icing, there's a quick alternative that is colorful and edible -- real flowers. Just verify first that any flower you plan to eat is safe -- a number of websites can help you with this.
Verify that the flowers you are using are edible and that they have not been treated with pesticides. If you have any doubts, consult an expert.
Wash your flowers -- gently! Then, using your paper towel, pat them dry. Spread them out on paper towels or newspapers.
Using your egg white or egg substitute and the food safe paintbrush, gently spread a small amount of egg white or egg substitute over the petals of your flowers.
Sprinkle your sugar over the flower. Gently lift your flowers and shake off excess sugar. Let them dry in a warm spot for about an hour. Assuming that you are using fresh flowers, they will only be good for a couple of days. If you are using dried or pressed flowers, you can store them in a airtight container for a few months. Keep them away from bright light.