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