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