This is a happy poop stamp I made for my nephews.

You will need stamp ink (other types of ink might work) and a piece of sponge or felt (I used a furniture felt pad). You can get these at a local store or if you want to support me I get a small commission  if you buy from the following links:

Stamp ink: https://s.click.aliexpress.com/e/_c2u7luzp or amazon https://amzn.to/4da3OJt  
Felt pad: https://s.click.aliexpress.com/e/_c2z7HdZ5 or amazon  https://amzn.to/4tZgt9m  

Just print the stamp with the poop design facing up and print the cover with the opening facing up, no supports required.

Enable ironing on the last layer, you can also use a fine sandpaper on a flat surface for better results.