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