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