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