 A cool trick that I learned through a PhD process was called the three things. It's a really simple process where every evening, once you're done with work, you write down for yourself in a special file or notebook three things that you have accomplished in that day and three things that you plan on doing the next day. It's really important to be realistic with these goals, so don't overdo it. The idea is that you always manage to accomplish about 70% of the goals that you set.