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