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