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