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