the answer is simple; take shotgun, saw off stock, sand down to smooth handle, then cut barrel to an easily handled size. then go into your mams bedroom and go through her knicker drawer (im sure you've done this already ) and take out one pair of tights, cut in half, put on your head.
borrow someones van. bring along cartridges as well as a drum of petrol and gloves.
go into bank/postoffice/securicor van, wave gun about, take cash. drive away. hide cash and gun, drive van down country lane set fire to van.
go cross country. sit in country pub having pint, get taxi to town, take bus