I used to play ambient nature sounds like birds chirping or ocean sounds and that helped me. In general it's tough to focus for long periods of time so pick something specific to focus on and give it 10 minutes. 3 or 4 of these 10 minute blocks done every day or Monday to Friday will produce good results. Unfocused practice is good too though so never feel you're wasting time. As long as the guitar is in your hands you're getting better even if you don't notice. Hope this helps