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