If like many people you have a limited amount of time to practise, use it wisely. For one week, focus on one thing. For example, if there is a particularly tricky passage in a piece you are learning, isolate it, slow it right down and practise it several times in a row without mistakes. This means you need to be focused but also very calm. Absolute precision is the aim, reinforced with accurate repetition until your brain and hands are consistently able to reproduce the techniques required. Always stop and correct any errors – go back and slow down again for successful consistency.