Improving one are of your life at the expensive of another may not be the best choice, unless you have consciously chosen to make this trade off. The idea of a Life Wheel is that you choose the areas that cover the most significant aspects of your life and put them as spokes on a wheel. You then rate yourself on each area and connect the dots to make a wheel. Here are two pictures to give you an idea.
I like to make things as simple as possible, so my Life Wheel has 4 spokes:
Mental
Physical
Interpersonal
Financial
These are the areas that are most basic that seem to cover all of the important areas of my life at this time.
Mental
In this category I include everything that is focused on my mind. This includes learning, vision and personal development.
Physical
In this category I include everything that is focused on my body. This includes health and physical fitness.
Interpersonal
In this category I include everything this is focused on deaing with other people. This includes relationships, family, partner and friends.
Financial
In this category I include everything that is focused on money. This includes career and money.
It is possible that my wheel is an oversimplification as there are some things that maybe don't fit exactly in these categories, for example environment and contribution from the above two examples don't necessarily fit exactly in the above four categories. You can add one or two more spokes, though I would think six spokes should be more than enough for most people.
I think these four categories cover at least 60% for most people and at most another two spokes could be added for a maximum of six, no need to make things too complicated.
You can see in the above pictures how each person has rated themselves on each area and then connected them to make a circular wheel inside the Life Wheel. These inside wheels are a little unbalanced and so that can give the person an idea of what areas to improve on, while still maintaining a balanced level in the other areas.
What does your Life Wheel look like?