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