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