I love the Pomodoro Technique.
Set a timer for 25 mins, do focused work until the alarm goes off. Get up, walk around, stretch, look out of the window, doing something fun.
Repeat as necessary. Three, four or five pomodoros can help you get most of your work done and can help avoid burnout. The most productive people don’t work long hours, they focus, get stuff done and rest.
Work plus reward can help you get over your morning hump. Try it.