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