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