Uninvited Guest

We have an unwanted and uninvited guest at our home.  His relatives have been here before but we have always been able to get them to leave in a timely manner.  Unfortunately, this time, our new guest doesn’t want to leave.  He’s quite comfortable in his new abode.  Apparently, we are feeding him well.  We don’t want to hurt him but this time, I think he is going to have to meet his maker.  It’s very aggravating to keep having to clean up after him.  He leaves his crumbs and shredded paper where ever he wants.  He’s very sloppy.  So, tell me please, how do I get rid of my new visitor?  If only I still had my cat, I know this mouse would be gone!!