Ok so every Pokemon has their own "base stats" which are set with every single one of that particular species. Never changes (save in later Gens when some get buffs and whatnot but that's irrelevant in this example).

Then we have the Pokemon's Individual Values (IVs for short, but in Gen 1 and 2 they were DVs. Same thing, really.), which range from 0-31 for each stat. These are random upon the generation of a Pokemon EXCEPT for breeding, which has a higher chance of passing down the IVs/DVs which the parents have. Since shininess in Gen 2 is determined by a certain arrangement of DVs, if you breed with a shiny parent, it's approximately a 1/64 chance of the exact DVs which the shiny parent has being passed down to the offspring.

I could give you the exact DVs which a Pokemon will need to be shiny but it's barely worth it when you can tell from just a single glance that a Pokemon in Gen 2 is shiny or not. There's nothing you can do in Gen 2 to speed up the process, it's just a matter of luck that eventually a shiny parent and normal parent breeding will produce a baby Pokemon whose stats match the shiny parent's.

(Also breeding two shinies together won't work in Gen 2). I hope this helps some. I'm not sure what your base knowledge on Gen 2 breeding is so I just started with the basics, so sorry if you already know some of this!