I love Philip Johnston's book, Practicepoedia. He gives beautiful descriptions of problems people have playing and how to solve them. Practice is the most important musical skill you can develop. Practice doesn't make perfect. Practice makes habit. You must be practicing in an accurate manner to get the most out of it. Some categories of help are "not wanting to practice", "learning new pieces", "preparing for performance", "getting your piece up to tempo", "staying focused", "saving time", and "dealing with problem passages".  Each of these categories have several different solutions. For example, if you don't want to practice it's not everything about practicing you don't like. It's usually small bits that you don't like. Perhaps you don't like practicing every day. Then schedule a day or days off. Perhaps you think it's boring; change the way you practice so each day meets the needs of your piece and add new ingredients to your practice to make each day unique. It's 372 pages of great ideas. Give it a try!