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