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