One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6)(7,8)(9,11)(10,12)(13,14,19,21)(15,23,17,20)(16,18,24,22)(25,26,27,28)(1,2,3,4)(5,7)(6,8)(9,12)(10,11)(13,15,19,17)(14,20,21,23)(16,25,24,27)(18,28,22,26)(5,8,10,9)(6,7,12,11)(14,21)(15,17)(16,24)(26,28)(5,7)(6,9)(8,12)(10,11)(13,16,19,24)(14,22,21,18)(15,25,17,27)(20,26,23,28)(5,7)(6,8)(9,12)(10,11)(13,17,19,15)(14,23,21,20)(16,27,24,25)(18,26,22,28)(5,9,10,8)(6,11,12,7)(13,18,19,22)(14,24,21,16)(15,26,17,28)(20,25,23,27)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.