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