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