Here are some essential chess tips that will help you understand the game of chess better:

• Developing the queen too early in the game is usually bad (see 1).
• Fight for the center. Remember, central squares are very important since they provide block posts for your pieces. Therefore, central pawns are considered to be more valuable than flank ones.
• Sometimes, it makes sense to give up a pawn to get an initiative.

• Always think twice before making a pawn move. Since pawns cannot move backwards it is very hard to fix "pawn weaknesses".
• Isolated central pawns are usually stronger in the middle game, but weaker in the endgame.
• If you have the spatial advantage, avoid trading pieces. If your opponent has spatial advantage, trade pieces to eliminate the advantage.
• If you have an extra minor piece, exchange pieces to increase your advantage. If you are a minor piece down trade pawns, not pieces (there is no way to checkmate with a minor piece and a king alone).
• Always play with a plan. Playing with a bad plan is a LOT better than playing with no plan whatsoever.
• By exchange active pieces of your opponent on your inactive once you gain advantage.
• Remember that knight is stronger in the center, bishop - on flank.
• Bishops are usually more valuable than knights.
• When there are a few pawns on the board, bishops are much stronger than knights. When there are many pawns on the board knights are stronger.
• Bishop pair is usually stronger than knight and a bishop or two knights.
• Rooks belong on open files.
• Doubling the rooks almost triples their power.
• Two rooks are usually better than a queen.
• In any stage of the game ALWAYS realistically evaluate the position. Do not underestimate or overestimate the attacking potential of your opponent. I know it is hard to do, but that's important. Some players overestimate the opponents attack considering that it is dangerous when it's actually not, and starts passively defend. Some players, in opposite, completely ignore any attack of the opponent and get checkmated fast.
• In the endgame rook activity is usually worth a pawn.
• In the endgame if you are down a pawn, do not exchange pieces.
• In the opposite bishops endgame, even if you are a pawn down it is usually a draw.
• In the endgame it is usually good to place a rook on 7th or 8th rank if you white and on 2nd or 1st if you black, attacking pawns and a king.