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