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