There are two ways, as far as I'm aware.
1) In Creative mode with a Wolf spawner, create one wolf (this will be an adult by default). Right-click with the spawner on the created wolf. This will result in a baby wolf; this can be repeated as many times as desired.
2) In survival/adventure mode, find and tame two wolves. With any raw meat in your inventory, feed both wolves once; they should have hearts above their heads and they will both mate, producing one baby wolf. By default this will be your pet. I think you can create wild baby wolves by feeding wild wolves one meat/bone in quick succession, causing them to mate and have a baby.
Note: If your dogs are sitting/in stay pose, right-click with a bone to make them stand and follow. They will not breed when sitting/stationary.
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No
You have to give it bones.
Not in the current Vanilla (Minecraft without Mods) Minecraft, no. But their are a few Mods out there that will make that possible.
You can't make a collar. When you get a wolf, they automatically get a red collar. You don't need to make a collar.
Kill a skeleton to get bones. You can right click a wolf with bones to tame the wolf. It might take as many as three bones to work.