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