Discipline is the key to improvement. If you are looking to make the summer great on the golf course, discipline will help get you there.
Just about everyone has a new years resolution, but only a small percentage follow through on it. Those who are disciplined get to their goal.
Set your golf goals and understand where you want to go with your game.
Set a practice schedule, choose good books to read, set up drills, etc. and stick to it.
Plan ahead, lay it all out and allocate specific time blocks to do the work that is going to make you better. I.e., Tuesdays and Thursdays 5:30 pm to 7 pm short game practice. Anything that comes up that interferes with this schedule needs to be rescheduled. Write it all out on a weekly planner in advance before your days get crazy.
Make this a habit. Look forward to it. Before you know it, it would be uncomfortable if you didn't get your practice in. That's how you become great.
Greatness can become a habit if you decide you want to take action and stick to it, but It's up to you on what you want to achieve. Apply this thinking to anything in life, not just golf.
"The successful person has the habit of doing the things failures don't like to do. They don't like doing them either necessarily. But their disliking is subordinated to the strength of their purpose.” - Albert E. Gray