One vertex per element, one color per generator, with an edge from x to x·s.
(3,7)(6,8)(9,10,15,20,16,21,14,32)(11,22,27,35,25,39,26,17)(12,28,30,36,13,19,31,18)(23,33,40,37,29,34,24,38)(2,5)(3,7)(9,11,15,27,16,25,14,26)(10,17,32,39,21,35,20,22)(12,29,31,40,13,23,30,24)(18,34,28,38,36,33,19,37)(1,2)(3,6)(4,5)(7,8)(9,12)(10,18)(11,23)(13,16)(14,30)(15,31)(17,33)(19,20)(21,36)(22,38)(24,27)(25,29)(26,40)(28,32)(34,35)(37,39) involution — undirected(2,5)(6,8)(9,13,16,12)(10,19,21,28)(11,24,25,40)(14,30,15,31)(17,34,35,33)(18,32,36,20)(22,38,39,37)(23,26,29,27)(1,3,4,7)(2,6,5,8)(11,25)(17,35)(22,39)(23,29)(24,40)(26,27)(33,34)(37,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.