Any small petals, grasses, leaves, buds, even some spices, or whole flowers
A few drops your scented oil

Dry completely. Add a few drops of your favorite scented oil in a zip-lock bag. Add all dry ingredients, close it. Then toss around to make sure it is mixed well and let it sit for three weeks, tossing bag about every three days. Then place in bowl.

To dry: Place petals, grasses, etc. on a window screen, place another window screen on top. Place in a hot dry area outside for a couple of days or until very dry. Try to avoid direct sunlight. It might fade the colors.