First off be careful to not let the dead body touch your stuff or yourself, burn any clothes after they have been in contact with the body, Put the body in a big sealed plastic bag, then put it in a big suitcase, add rocks to the suitcase. Put the body into your car boot, drive upto a remote Scottish Highland village ensuring it has minimal or no CCTV. Buy a rowing boat in cash. Drive out to a remote bit of coastline put the suitcase into the boat along with fishing equipment as a cover story, row out into the ocean for 4 hours and dump the body the rocks will ensure it stays at the bottom of the North Sea and doesn't wash up onto the coastline, row an hour back and then dump the Murder weapon, row back to the car, drive to a remote location in another part of the highlands at least 4 hours drive away, burn the small rowing boat and your clothes, change into fresh ones and drive back to your home.