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