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