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