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