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