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