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