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