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