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