If you are looking to improve the quality of your life you should start by congratulating yourself. Just the fact that you aren't in denial about your life and have the courage to admit that there are things that need improvement is a big step and something most people aren't willing to do. We all know that our lives could use some improvement and by starting to take action in the needed areas, we can reap the benefits of our work later on.
The first thing you need to do is off course to figure out what you want to improve and specify it as concretely as possible. The reason for this is that you want to be able to measure whether or not you are making improvement in that given area. This doesn't mean that you should quit if you don't get the desired results immediately, it just means that you should change your course slightly until you are getting the results you initially wanted.
The next thing you want to do in order to improve any area of your life is to make a decision. When you make a decision you cut of the possibility of failing and you know deep within your heart that no matter what you will make things happen by taking constant action and adjusting your actions when needed.
You also need to make a roadmap you can follow. This roadmap will keep you focused and dedicated when needed and you will always be able to get a quick overview in times of feeling like quitting. Something that is really important when you start working towards your goals is that you actually take the time and enjoy working towards your destination instead of focusing solely on where you want to go. By enjoying the process you will grow as a person and reaching your goals won't be a constant struggle where you have to push yourself.
The cool thing about having the mindset of enjoying the overall process is that you don't have to wait until you have reached your final goal in order to improve the quality of your life, instead you will actually feel an improvement immediately solely based on the fact that you know you are working towards better times. Last but not least, you should get started as fast as possible and just go for it.