So, my usual planning ideas are:
-to put my left opponent's pieces under attack, so that any other player could attack him later (and so, organize double attack)
-to pin my left opponent's pieces by the use of other players' pieces
-to supress my left opponent's pieces activity by my pawns and knights (and sometimes by attacking queen's squares by my minor pieces)
-to not attack my opposite very early in any game (maybe just to mate him in 1), at least until for becoming really stronger than my left opponent.
-to weaken my opposite just before we mate someone other
-to not allow any checks on my king or attacks on my queen (as much as possible), especially by player from the left
-to push my pawns for queening usually only after my left or right opponent's is mated or seriously weakened or very busy
-to clear routes for my rooks by attacking with rook pawns
-to clear routes for my bishops by moving my pawn structure
-to achieve solid pawn chains
-to castle only if my king's castle cannot be attacked by some pawns or be pinned
-to evacuate my king in safer place
-to maneuver my knight for gaining some kinky forks (usually in closed positions) and to weaken opponent's king's defense (usually in open positions).
So, since I wrote it already somewhere in this forum, I'll post it here.
This is the list of my strategic ideas (by "strategy" I mean "thinking in long terms") in 4PC.
Add your own!