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