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