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