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