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