Paint two coats of chalk paint on each pumpkin using the brush. Let dry between each.
Add Mod Podge to the areas that you plan to add Diamond Dust. Sprinkle the glitter directly on the wet Mod Podge (it will dry clear).I worked about 1/4 of the foam pumpkin at one time. You'll paint down the sections of the pumpkin and then move onto step 3.
Repeat until all areas of the pumpkin that you would like to accent are covered. Let pumpkins dry completely before displaying.
Video
Notes
I had Matte Mod Podge in my supplies photo but I ended up changing it to Gloss Mod Podge to make the Diamond Dust area a little more shiny.