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