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