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