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