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