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