Golden Buff. . . . Is that another term for Gold Sex-Link?
If so, basically breed the two, but if your Ameraucanas are actually Easter Eggers then be sure to use hens not roosters and make sure that they lay blue eggs, not green, otherwise you'll lose color in the next generation.
Another thing - Sex-Links are good producers because they're hybrids, so breeding them to anything else but a purebred good producer won't gaurantee great results of production, but still will give decent production. If you truly want something to lay like your "Golden Buffs" you're probably best to breed the Ameraucanas or EE's to a Leghorn, Production (rhode island) Red, or production-type Australorp.
That aside, the next generation if you're satisfied, that's that. If you want to continue on, then the best thing to do is select the bluest or more green, less brown hued layers with best productive results and breed them to what you choose, but with a parental record or gaurantee in good production. Breeding to another brown egger makes more brown and greenish eggs. Breeding to a white saves color but just lightens it. Breeding to a green/blue saves the blue/green egg color.
