Potpourri can take many weeks to dry, but you can have fun creating a mixture that smells good right now.
Do this activity whenever there are fresh flowers blooming. It's particularly fun to do in early fall, to capture a bit of the summer before the cold temperatures arrive.
If you have flowers in your garden, pick a few to snip. If you do not have a flower garden, tell neighbors about your project and see if they will let you take a sampling from their gardens. Always ask permission before snipping.