Indeed, the lenses of the high prescription eyeglasses are thick which may make you look nerd. But you can choose the frame eyeglasses with bright color to light up your complexion. Or you can choose to wear the clothes that are matched with your eyeglasses. There is another advice. You can wear the contact lenses which will make you look beautiful with big eyes. But you should keep the good habit of hygiene.
In my opinion, you can consider your glasses from your face shape and the color of skin, we all know that the image of the glasses depends on your face shape and the skin color and they will determine the best sunglasses for you. For example, if you have an oval face, maybe you should choose the oval frame which will match you. At the same time, you should consider your skin color. You'd better choose a style which can make the whole image not so weird. In other words, it's a big deal to decide which glasses will suit for you. On the other hand, as you have described in the question, you don't want to look like the nerd, you can also try some light color when you choose the glasses. And also can wear some clothes which can make you look more active.