After castling, my preference is to have 3 pawns lined up on the 2nd (or 7th) rank. Then I move the pawn on the outside file (A or H) forward 1 rank to give the king an escape hatch if needed later in the game. My king generally sits behind the middle of the 3 pawns.
I know this sounds pretty standard, what are some other preferred set-ups out there for protecting your king?
King Position After Castle


Dont forget the king is an active piece too. Depending on what your opponent has left on the board it can be useful to bring him to f1/f8 later in the game to stop a rook coming down the open e-file to e1/e8

If I can trade enough pieces off the board and end up position or pawn up....sometimes I don't castle at all....some games I even let the opponent trade the queens off and recapture with King if I'm up a pawn and can still defend. I know my weird style isn't for everyone, but sometimes it is an advantage to have a central King later.
I know this sounds pretty standard, what are some other preferred set-ups out there for protecting your king?