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