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