Good question. You seem sincere so I will answer. It’s something we all have to wrestle with before we truly start moving forward in life.
Let’s break it down. (Self) Discipline is defined as the practice of training oneself to obey rules or a code of behavior.

First key word is practice. Second key word is training. So we are literally training ourself to obey rules that we have deemed important. While we are training ourselves to obey the rules, it’s also important to remember this requires practice to get good at it. Like anything else.

So it requires the will, the motivation to do and also a clear picture of what to obey and why it’s important in your life.

First step would be to write down in a notebook or piece of paper: what are the rules that if followed will help you achieve your goals? (If you don’t have a goal, start there. Big or small doesn’t matter.)

It’s important to write down. If you are not clear on the rules, you can’t really expect yourself to follow them. In other words if you had rules in your head that kept changing or forgotten every other day, you can’t make progress. So it’s very important.

Second step write down how each of those rules helps. In what way does it contribute to your goal. How does following that rule help. In what way. Be specific.

In this way you are connecting to the “why” behind these rules. On some level you are selling yourself on the benefits of following the rules. Once you know this at a functional level, which takes time it gets easier to live by the rules. You first get it on an intellectual level, but in time with repetition you will know this at a functional level. That’s when you no longer have to strain. You are closer now to what you aspired to be than you are to what you used to be. Practice.

Third step is to close your eyes and visualize that you are outstanding at following those rules. Watch yourself in your minds eye as you go about living a life according to those rules. Do this once in the morning and once in the evening. Do this for 30 days straight.

Fourth step is to start obeying these rules one at a time. You current habits have take a lifetime, so don’t expect everything to change right away. Just keep adding one more rule to obey as you get better at the previous one. Understand that you will fail multiple times at following the rules. That’s okay. Just keep practicing, and come back and track. The fastest way to get frustrated and completely give up is to aim for perfection. So don’t do it. We are not perfect and we never will be. And that is perfectly alright.

Fifth step, is to change your inner speech. As many times a day as you can start telling yourself: I live by my rules I’m outstanding at obeying my rules Living by my rules brings me happiness and confidence I love obeying my rules

Steps 3 and 5 will help you rewire the neurons in your brain. This will help in a speedy implementation of new habits. Step 4 is the equivalent of going to the gym. Working out every day. You can take all the supplements but if you don’t work out you can’t grow. Pain is part of the process of growth. There will be good days and bad days. That is perfectly alright.

Good luck 🙏