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