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