Now there is the permanent way for your eyes to look in different color with no wearing of colored contact lenses. That is the surgery of changing the color of your iris. Now this surgery becomes more and more safe and effective. The number of optional colors becomes more. You could just go to the famous hospital to have a result.
Generally speaking, there is not any other normal way to change your eye colors without wearing colored contact lenses. This is because the eye colors are determined by the amount of pigments in the iris of your eyes, which is decided by the heredity of each individual. In some cases, some people get color changes in their eyes when they are growing, but when they reach a certain age, their eye colors will not change any more. If there are no gene mutation or other pathological change in your eyes, then your eye colors will not get changed colors. However, there is a very rare method to change the eye color, that is, liquid injection in your eyes, but it is very harmful for your eyes, thus it is not recommendable.