You can do both.
If you train it to level 100, you can use a reset bag and horde train, which is infinitely easier than super training. The only downside though, is training it to Level 100.
If you Super train at lv. 1, it will be harder to EV train it because of its low Sp. A or Atk. If you want to go this way, I suggest feeding it Carbos/Iron etc. to get a head start on stats.
If you EV train at level one, you may notice that its stats don't change. Don't worry about that, as they will increase more as you level up after fully training it.
Source: Experience
