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