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