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