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