You can use trash bags to make amazing Halloween decor! Trash bag spider webs are a fun and easy project. Cover your porch in spooky spider webs with this easy tutorial (step by step instructions and video tutorial). Could be white bags too!
Light-Up Ghostly Witches / It’s a toss-up whether a pumpkin or a witch glowing in the dark is scarier. But a coven of three ghostly witches floating around with a soft glow will beat a pumpkin any time of the day or night, including on Halloween
How to make a lawn ghost - this is a really inexpensive and adorable idea for Halloween lawn decorations. I might have to add faces to mine, but I'm thinking of something like this for my lawn this year.