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