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