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