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