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