Wow. Seems so different from the 5th gen stuff I'm used to doing. It's not hard finding Shiny Eggs with the nature and ability I want in 4th Gen. However, what do I do after that for the RNG abuse of the IVs? Is that some sort of separate seed? I suppose it's like combining both aspects of the egg articles here on smogon (the breeding shiny and breeding flawless). I just couldn't find an article that mentioned combining the two. Thanks so much for the replies btw.
EDIT: So IVs are generated once you take the egg from the daycare man?
Yeah, in 4th gen the IVs are not generated until you pick up the egg. Everything else is generated when the egg is made.
Once you have the egg made, you save in front of the daycare man, and then you hit the seed that will let you get the IVs you want.
Here's an example. Let's say I want a shiny Timid Drowzee with IVs of 31/0/31/31/31/31. I want it to be Male and have Insomnia.
So first thing I do is save the game with my 2 parents in my party in front of the daycare lady. We'll say that a Ditto is Parent A and my Drowzee is Parent B.
Now, I need to find the right PID seed to get Timid, Ability 0, M and shiny. I input my ID/SID in the shiny egg finder, and put in a delay range and my info and find an appropriate seed. Generally you want to use Frame 1 for ALL PID seeds. Otherwise you will have to reject eggs until you get to the shiny one (aka hassle). So once I find a Frame 1 shiny PID that fits my needs, I will put that in the Seed to Time window and hit my seed. Once I turn on the game, I deposit parent A and B in the daycare (in that order) and bike around until the Daycare man has an egg.
Then I save the game in front of the daycare man. Now I look up a seed I can use for IVs. I put in the IVs of Parent A and Parent B in the boxes, and also fill in my desired IV spread. I usually search Frames 5-10 for this part. This is because there is a wandering NPC on the route that may make your starting Frame for IVs > 1. The inheritance does come into play here. If my target spread is 31/0/31/31/31/31, I need my parents to have any combination of 3 of those IVs. I think you know all about this from 5th gen breeding.
For this part, you need to open the Pokegear as fast as possible and after you do your advancing, close the Pokegear and pick up the egg as fast as possible. But in general you just advance to 1 frame before your target, and then pick up your egg as quickly as possible.
There are some other details here like how to check your seed and advance the frame, you can find that in the RNG help guide at the beginning of this thread.
I hope this helps.