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)(24,25)(26,28)(5,7,10,8)(6,11,9,12)(13,14,17,22,18,21,16,19)(15,20,23,28,24,27,25,26)(2,4)(5,6,10,9)(7,12,8,11)(13,15,17,23,18,24,16,25)(14,20,22,28,21,27,19,26)(5,8,10,7)(6,11,9,12)(15,24)(20,27)(23,25)(26,28)(5,9,10,6)(7,12,8,11)(14,21)(19,22)(20,27)(26,28)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.