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