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