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