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