Depends on what you want and if you have the ability to check ESV/TSV and such yourself. I don't have the ability to check it myself, so I prefer to breed for a box of eggs, check their IVs and if they're flawless and reset if they are, I then put them in a box specifically to have their ESV checked by someone who can. I then check the lists I have available to me (specifically the one on the
shiny value thread)to see if someone has a TSV that matches any of the eggs I had.
A thing I like to do is to put a specific combination of markings on the egg, and list the eggs I have and what they're marked with a place on my trade thread.
If you can check ESV's yourself, you can just check the IVs and such while you're checking the ESV's.