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