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