The following is a list of personal development areas to improve in your life. This is an high level list of areas to improve, and each element is equally important to improve your life. I recommend that you constantly work on each of those.
This area is about your body. Developing good health means to eat properly, exercise and stretch your body. Having good health is probably the most important thing you can improve in your life. Start by going out and exercise every day, I recommend to do at least 15 minutes of it every day. After that, when you feel comfortable you can move to 30 minutes a day. It's important that you work both on your strength (body building, crossfit) and in your endurance (jogging, bicycle, etc.). As long as you make the habit of working out each day, start to follow a diet. There are literally thousands of diet plans available. Became an expert on the topic and try different things to see what works for yourself.
It is of course fundamental to have enough money to live in a comfortable house and maintain your family, or just to follow your dreams. For this reason is important to develop your finances until you reach financial independence. To make that happen you need to build a series of passive income systems that generates money for you every month. This kind of systems is usually difficult to develop at first, but after it has been done, its rewards are high. Depending on your positions, there may be many options available to you, but if you are already comfortable using the internet (and you should if you are reading this), I suggest you to try internet marketing.
Chances are that you need to talk with other people every day. It's crucial for your success to develop your social skills at a very high level. You may think that developing sociability skills is like cheating and you must be born with that ability if you want to build genuine relationships. In reality this is not true and socials skills are just like any other skill: you can learn it, practicing it without cheating because what you do is still genuine and in you are really interested in it.
Spirituality may be misunderstood by the majority of us. Spirituality does not mean going to the church or praying a lot of times. Developing spirituality skills means to improve your self being and to learn how to control your emotions. Spirituality can dramatically improve the quality of your life in the long run, so be sure to spend a minimal amount of time each day in this area.
If you want to change, your habits have to change. Try to select one single habit per month, and work on it every day for the entire month. Many people when they first hear about personal development, want to change so many things in a short period of time. This tactic does not work because you'll be giving up after a few days. Instead, work on one single habit per month, and do it well.