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