You don't, legendary Pokemon can't be hatched from and egg with the exception of manaphy and phione.
Ditto and Lugia do not breed. I tried it.
yes you can. but if you have Pokemon soulsilver, the first encounter will be a lugia and vice versa for ho-oh.
Lugia
Yes.
lugia
Whirl Islands!
pokemon piatunum lugia egg code
If you mean Lugia following you, yes, it can.
You can't unless you use gameshark
lugia
A person that has SoulSilver
Lugia is the only one.