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