My inspiration on the left and my art on the right:
So for this, I used small brown paper bags I bought from Michael's. As well as an autumn theme stamp, some ribbon, and loose leaves from Joann's. All of these items were on sale for about 60-70% off. I also distressed the edges with black paint and a sponge brush.
I also made bigger goody bags for my son's classmates. We aren't allowed to give food/candy so I needed bags large enough for coloring books and crayons.
So for this I used the same stamp, plus different ones on top with heavier ink, painted on Halloween themed creatures with a paint brush and a stencil, also distressed the edges, and hole punched the top & tied it with raffia left over from my son's birthday party.