Well, you should know that there are no natural ways to change the color of our pupils, since it is decided by our genes you know? So, if you insist on making them look greener. I can only recommend buying colored contact lenses, and there are a lot of contacts of different colors at large eyewear stores, including Walmart, typically, a pair of them would not be too pricey, you can buy them within 100 dollars.
If you want your eyes look more green, the best and quick way is to wear green contact lenses. So, just move, buy green contact lenses. Even if you have vision problem, you can buy prescription colored contact lenses. There are many brands provide green contact lenses with prescription lenses. You can have a look at 1800contacts.com. Good luck.
I recommend you two ways to make your eyes look greener. On one hand, you can wear green contact lenses. When you wear them, it looks as if your eyes are green. On the other hand, you can use some green eye shadow and draw green eyeliner. If you use them, it will make your eyes look bigger and greener.
I think both of dark brown eyes and green eyes are beautiful.However,if you want them to look greener,it's also easy to come true.You could buy eyeshadow colors that are for green eyes.Also you can make your eyes greener by using a little bottom eye liner and put some on the top and then use eyelash lengthening mascara. By the way,dark brown or green eyes are not the essence.The key point is that you should be confident of yourselfï¼