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