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