It’s Halloween on the 31st October.
Exactly how do you celebrate Halloween and what is wrong with the specific actions you are taking. Dressing up, share candy, playing tricks etc. As far as I know, people do not perform any prayers or rituals venerating Satan or other mystical beings (not that it actually matters). Celebrations bring communities together, give people an excuse to get together and enjoy each other’s company.
On the other side, you need to think about what are the consequences of celebrating un Islamic traditions. Where do these laws forbidding Muslims to celebrate other traditions come from? Is it specific stipulated in the Quran or Hadith, (for those who follow these fairytales)?
All actions have consequences. Good actions have good results, bad actions have repercussions. We are generally aware when we are doing something good or bad but religion has a way of clouding our ability to decider between the two because of all the Mythical rules we are lead to believe.
So before deciding to do or not do something, have a think about what is forcing you to it or not do it? What are the consequences? If it is not clear then you should just use your god given conscience to guide you.