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