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