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