We luckily never had to sleep train, but we set a solid bed time and routine at 6/7 weeks that I think has helped. We tried to limit the number of transitions, so they were put down in their cribs from day one for night even if they didn't end up staying there.
We also did what Eddy said -- we let them get to actual crying for bed and night wakings. Fussings and even a single cry-out, we still don't go in for.