For the record, Halloween is not a Norwegian or European tradition so we don't do a lot around it. Kids have been very keen though: they are looking forward to unlimited access to candies!
However, some people don't feel connected to the tradition and don't wish hordes of kids knocking at their door. To make it easier for the children to know where they can "treat or trick", a "rule" has been followed the last years: they can go to the houses which have a lighted porch and any kind of Halloween decoration, it could be a single pumpkin or more.
I needed to put some kind of spookiness to the front door, but it had to be quick and simple. Here is an easy option:
I folded the paper sheet in the middle and draw one half of a bat.