We got a great color chart from this source:
Black-Black, Blue, Chocolate, Lilac, Otter, Sable and Seal.
Broken-Broken, corresponding colors from the chart.
Californian-Californian, Black, Chinchilla. Sable, and Seal
Chocolate-Chocolate, Black and Lilac
Lilac-Lilac and Black
Lynx-Lynx, Lilac, Opal, Red, and Castor
Opal-Opal, Castor, Lynx, Red, and Otter
Otter(Black, Blue, Chocolate and Lilac)-Otter(Black, Blue, Chocolate and Lilac), Black, Blue, Chocolate, Lilac, Castor, and Opal.
Red-Red, Lynx, and Castor
Sable-Sable, Black and Californian
Seal-Seal, Black and Californian
White-White, any other color but will introduce white toenails into the line. Carries an albinism gene which affects eye sight (blindness).
Colors to breed together are basic. Self to self, agouti to agouti, shaded to shaded and the tan pattern to the tan pattern. Study the pedigree on your rabbits. I am in hopes that you have purchased or received stock from a reputable breeder and can search the pedigree for color combinations that will help you start your own successful line of Rex.