One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,7,8,5)(9,10,13,20)(11,22,24,16)(12,18,15,19)(14,29,28,32)(17,36,38,25)(21,27,39,31)(23,34,26,33)(30,37,40,35)(1,3)(2,5)(4,8)(6,7)(9,11)(10,16)(12,26)(13,24)(14,25)(15,23)(17,32)(18,34)(19,33)(20,22)(21,35)(27,40)(28,36)(29,38)(30,31)(37,39) involution — undirected(9,11)(10,17)(12,23)(13,24)(14,30)(15,26)(16,32)(18,37)(19,35)(20,38)(21,33)(22,29)(25,31)(27,36)(28,40)(34,39) involution — undirected(3,8)(5,7)(9,12,13,15)(10,18,20,19)(11,23,24,26)(14,27,28,31)(16,33,22,34)(17,37,38,35)(21,29,39,32)(25,30,36,40)(9,12,13,15)(10,19,20,18)(11,23,24,26)(14,27,28,31)(16,34,22,33)(17,35,38,37)(21,32,39,29)(25,30,36,40)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.