This will be as brief as possible but here is the basic procedure that works here. Start them as young as possible. A scotch comb is my best friend. Stay close / follow the calf gently trying to touch /scatch his tail head. Once you connect, He should love that. This is important:, when you are able to get a few scratches in, then YOU walk away before he decides to. Take a few days doing this til its a non threatning routine. Next start carrying a halter with you. Start combing / scatching while placing the halter on his back, neck, face. Do not put it on him yet. Take a few days with this routine also. At some point after he is used to this rope thing place it on him VERY loose. If he wants to slip out if it let him. Again, a few days with this routine. At this point I will not touch him with the comb or even scatch him unless he is in the halter. No more freebies buddy!! Slip the halter on and off a bunch of times only combing when haltered. Usually around here its at this point he is offering his head up, "halter me!!" Now to lead...... A slight steady pull, do not turn this into a tug if war. You will lose. When he advances a foot, let off the pressure right away. Loosen the halter if it has tightened. Repeat. Repeat. Repeat. This can take an hugh amount of patience. I WILL NEVER USE A TRACTOR. Did once and never will again. You WILL hurt that calf. Remember, these are living and breathing creatures.
Now the other forum members will be all over me about breed, age, brute strength etc, and thats ok. But this is how I do it. Just so ya know, I too, have been put in the hospital by some halter breaking practices I no longer do. For the last 20 odd years, my goal is a "trained" calf rather than a "broke" one. Good luck to ya!