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