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