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