Collect two tokens from participating newspapers, stick them to a form you get from the website, hand them in at a staffed station to get your Rover ticket, then travel all day for £10. Or make a weekend of it for £17.50.
You can travel anywhere on the Northern Network on any day (Mon-Sun), however, if you like your vintage Diesel Hauled trains, you can catch the 10:04 from Preston (Mon-Fri) all the way to Carlisle (via Barrow, arr Carlisle 14:26) along the spectacular Cumbrian Coast, hauled by some DRS Class 37's on lease to Northern. Spend a few hours in Carlisle then either travel back along the Coast again or pay extra for the Virgin Pendelino along the WCML.
See here for Class 37 workings:
w w w .class37info.co.uk/sum2016.aspx
Pro-Tip: if it's a hot day, be prepared to sweat like a pregnant nun; the coaches are Mk.2's which have no opening windows, instead they rely on cooling from the engine, but when I went in July this didn't seem to be working.
Travel up to 21st November, so the inverse problem may be apparent.