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