For an introductory tour follow the A684 to Kendal then take the B5284 via Crook to Windermere lake.
Turn right and follow the A592 through Bowness then on up through Troutbeck to Kirkstone Pass (watch out in winter, this road quickly becomes impassable). Drop down through Glenridding and along the shores of Ulswater (perhaps stopping for a cruise on the lake) to eventually join the A66 at the Rheged centre near Penrith. Throughout the tour you will find many places to stop and admire the view, take a stroll, or to have something to eat. Return to Sedbergh via the M6.