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