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