Lots of them:
Candy - "(The boss) was sure burned when you wasn't here this morning. Come right in when we was eatin breakfast and says, 'Where the hell's them new men?' an' he give the stable buck hell, too."
The boss is automatically skeptical about George and Lenny traveling around together, especially since George holds Lenny's work card.
The best example is the first meeting of Curley. Curley starts picking fights with George and Lenny during their first conversation because George is doing all of the talking. Candy has a brief commentary about Curley picking fights with everyone.
Then, of course, we finally meet Curley's wife who is out looking for Curley, as usual. Candy gives us a great description of a pretty wife who already has the "eye" - whose pants are full of ants. There's a great section of foreshadowing here where George warns Lenny about staying away from Curley and his wife as much as possible.
With the exception of how cordial Slim and Candy are, most of what we see in Chapter two alerts us to the impending doom of the novel.