EV / IV legality

[DRatJr]

Ok so lets say I raise my pokemon to level 100. If I change his EVs to my liking, will that effect his legality? Or no?

Also, how do I edit the IVs and Nature of my poke, while keeping him legal?

Also, do EVs effect a pokemon as they grow, or just the stat at the end? Like should I put the EVs on him att LV 1 or LV 100 or does it not matter?

[ReignOfComputer]

1. No.

2. For DPPtHGSS, you need to generate a PID for A-B-C-D (or none if hatched). For BW, leave the PID field blank after editing and PokeGen will automatically generate a random PID for you.

3. As they grow.

[DRatJr]

Ok so after one is freshly hatched, put in my EVs and raise it. Got it.

For IVs (B/W), can I just change them to what I want, and change the nature, and just save? Will it be legal then?

[DRatJr]

Ok so I guess I change the IVs to what I want, then the nature and ability. Then I go in PID finder and put in the same values I had, and hit ok to Generate it. Right? And will it always be legal?