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