Maintaining a balanced life has been revealed as a secret to happiness. As for me, I realized this after trying different versions of unbalanced life. I had a life when I was living in my relationships only. Another time I was at the point of working too much and not spending enough time with my son. All my life I had a habit of switching from one extreme to another.
Only recently I succeeded in maintaining the balance in my life, which was the only way out for me from the burnout I got by a previous approach. But don't get excited yet - even when you get to this point and feel it - you still can lose it at any time, any day.
The secret of balance is in its maintenance. If you just did something once or for some time - it does not mean that now you get it, you know the secret. You do know it but if you stop practicing it, you lose it. Imagine, that you are balancing on the rope : what happens if you just decide : "Ok , got it", and relax - you would lose it and fall.
This is how we are wired: we are supposed to balance physically and mentally. To make it easier at some point, good habits become of a big help as they automate our balance.
This is what I did. I devoted different times of each day to particular activity, like early morning time is my personal development, my son's school time is my prime work time, one hour before school pick up is my fitness time, after school is my family time.
It sounds pretty straight forward but a tip here is to focus on just one activity. For example, I don't look into my work during my personal development time, because I don't want to start my day solving some business problems as I did before. I start my day by clearing my mind, setting my goals, reading and writing. This way I am ahead in whatever happens next.
There are days when you lose balance. We are not perfect. Although try not to extend this to more than one day, try to get back right the way and forgive yourself if you stepped out.