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