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