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