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