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