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