Chess is a very complex game. There are some tactics that are very simple yet world masters use them.
Pressure on your pieces[]
Your pieces can't have to much to do. There is a weak spot in both armies: f2 for white and f7 for black. The reason they are weak spots is because they are only protected by the king so if the pawn on that square is captured, only the king can recapture the intruder. That is why a type of mate called blitzkreig invoves those weak spots.
Pins, forks, and discovered attacks[]
pin, fork, and discovered attack are simple tools that can be used to aid your chess. Forks are when a piece (or pawn) attacks two or more pieces. One will get away (usually) but one will be captured (again, usually). Forks are especially powerful when they involve a king, queen or both. Knights are renouned for their forking ability since they can jump over pieces and their unusual movement. Pins are when a piece (either rook, bishop or queen) puts a piece in a position it would expose a more valuable piece. The two types of pins are relative pins and absolute pins. Relative pins are when the exposed piece isn't a king and exposed and absolute pins is when the exposed piece is a king.