Quick method to improve for beginners

what about these basics?: controlling the center (d4,e4,d5,e5), castling early (king in the center is suicide), capturing towards the center, moving the queen out of the way to "connect" the rooks, developing rooks the the d and e files, taking advantage of open files, don't neglect passed pawns.
of course these aren't hard and fast rules, but they can be guidelines. the important thing to remember is that most of the action takes place in the center (with the exception of closed positions). if you're up in material, trade pieces. if you're down, trade pawns.

Only Bishops, Rocks and Queen are able to pin a piece, once they are gone from
the game, you don't need to woory about pins any more.
If you have "nothing" to do in a game place your rocks on lines or rows, your
bishops on diagonals opposite opponents pieces (White Rock d1 Black Queen d6,
White Bishop d3 Black King h7 for example), regardless how many of your OR
opponents pieces are in between. Tactics come out of those positions often
by themselfs, you can also paly for the removal of the enemys pieces.
Next method of doing nothing: improve the position of your king, either
making it more secure or by advancing your king towards to enemycamp.
If you exchange pieces next, your king has an advantage by being closer
to the center, a few tempi are enough to win an endgame with equal
pawns. Of course you can only advance your king if it is save.
The method of adavancing the king works in four out of five games, where
I employ the plan, in the fifth game my king gets into trouble, mostly against
strong players. They see throughsuch things...

Just to add Mr.Wizard's note :
Always place your pieces in position which is protected by / tied to at least one or more other pieces unless you are in attacking position or preparing sacrifice to gain psoitional advantage. Believe me this will make beginners to stand longer when facing much stronger player, though this may lead the game to more dull or positional play...
One of the skills that strong players have is the ability to see all captures within a few seconds [or less] The variant of chess called 'take me' chess, suicide chess or 'loser's chess' is an excellent way for beginners to spot all captures quickly. I suggest the version where the punishment for not seeing a capture is instant loss! i.e no telling your opponent..."have to take"
Other 'rapid skills' you must develop are spotting checks and assessing the danger posed by them quickly, as well as spotting moves that put any piece in danger. This doesn't mean you should play such moves...but you must make a mental note of such moves before moving on to the more exciting challenge of the quest for 'tactical shots' such as double attacks, discovered attacks etc etc
Others might like to add their suggestions to this framework of very basic, but important skill-set.