You can't, they're always boys.
If you want them to get an egg- heres how. After you complete the pokedex, you get a new one wth ALL of the Pokemon- not just Sinnoh Region (I think that's how you spell it) The you go to the little patch of grass right before Canalave City. Then seach, and search, and search then you will eventually find a Ditto. Ditto can make eggs with any Pokemon (exept legendS) even boys. Hope I helped!
you get the manaphy egg in Pokemon rangers and send it into Pokemon diamond or pearl
in hearthome city
Migrate from FireRed or LeafGreen. (Unobtainable in Diamond and Pearl.)
Eat your starter and then you vomit up a whismur
You have to have Pokemon Ranger and do the quest for the Mysterious Egg. Then you can transfer the egg over to Diamond, Pearl, or Platinum.
Cynthia does not give you an egg in Pokémon Diamond or Pearl, she gives an egg containing a Togepi in Pokémon Platinum after you have beaten Team Galactic in Eterna City
Once you have traded the manphy egg to Diamond or Pearl, restart the game and go to any pokemart. There you receive your manphy egg.
you dont you get a cleffa from diamond/pearl,and or platinum
The only way to get a Manaphy is to beat Pokemon Ranger, do the bonus mission where you save a Manaphy egg, then transfer the egg over to Diamond, Pearl, or Platinum, then trade from Diamond, Pearl, or Platinum.
Get two Pikachus (Boy and girl) from Pearl/Diamond/Platinum and put them in day-care. Even if Pikachu is warm blooded it still lays an egg. The egg will hatch into a Pichu!
Yes, you can send the Manaphy Egg from Ranger Net to either Diamond or Pearl.
No it does not get you a bad egg