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)(25,26,31,29)(27,34,32,28)(30,33,39,37)(35,38,40,36)(1,2)(3,8)(4,6)(5,7)(11,19)(15,16)(20,24)(21,23)(25,27)(26,28)(29,34)(30,35)(31,32)(33,36)(37,38)(39,40) involution — undirected(1,3,5,6)(2,4,7,8)(9,11)(10,15)(12,20)(13,21)(14,19)(16,18)(17,23)(22,24)(25,26,31,29)(27,28,32,34)(30,33,39,37)(35,36,40,38)(1,2)(3,4)(5,7)(6,8)(9,11)(10,16)(12,20)(13,23)(14,19)(15,18)(17,21)(22,24)(25,28,31,34)(26,32,29,27)(30,38,39,36)(33,35,37,40)(9,12)(10,17)(11,20)(13,18)(14,22)(15,23)(16,21)(19,24)(25,29,31,26)(27,34,32,28)(30,37,39,33)(35,38,40,36)(1,4)(2,6)(3,7)(5,8)(9,13,14,17)(10,12,18,22)(11,21,19,23)(15,20,16,24)(25,30,31,39)(26,33,29,37)(27,35,32,40)(28,36,34,38)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.