(a) Goal #1: be aware of loose pieces on the board at all times. The Black bishop at c6 fits that description. (b) Goal #2: be conscious at all times of any checks you can give. Here there are two: Qd3 and Qc2. (c) Goal #3: look for any ways a check can be combined with an attack on a loose piece. Here Qc2+ attacks and wins the bishop.