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