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