Satan was cast out heaven alongside with his angels.
Earth was the only place or option satan had..so he came straight to the earth and started living in earth...
Revelation 12:9 (KJV) And the great dragon was cast out, that old serpent, called the Devil, and Satan, which deceiveth the whole world: he was cast out into the earth, and his angels were cast out with him.
but he was just roaming around the earth.
Job 2:2 (KJV) And the LORD said unto Satan, From whence comest thou? And Satan answered the LORD, and said, From going to and fro in the earth, and from walking up and down in it.