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