Ok, good question. When you're getting the shininess and nature, you can call Elm as many times as you want. If you match up 10 calls, then you know you are on the right seed, so then put your parents in daycare. After that, bike up and down until the daycare man has an egg. This egg will be frame 1. Tell him you don't want it, and keep biking until he has another one. This one will be frame 2, so tell him you don't want it. Keep doing this until he's on the 5th egg, which is the one you actually want. When he has the 5th one, save in front of him and turn the DS off so you can RNG for IVs. When you RNG for IVs, each Elm call advances one frame, so you have to be careful.