Butterflies are likely the most photographed of all insects, having a built-in "WOW" factor. But just because they already make an attractive subject as they are, it doesn't mean we shouldn't try to get creative with them.
Whenever I photograph butterflies I try to portray them in unusual ways, whether it's the angle I use or the lighting. Backlighting, for instance, might not be ideal in terms perfect lighting on the butterfly itself, but it offers unique opportunities to create an unusual image, emphasizing the silhouette and the transparency of the wings. Samples here and here. Another technique I often try is slowing down the shutter speed to get nice blurring of the wings in motion.
Creating an interesting composition is another element to pay attention to. Don't just be satisfied by placing the insect always right in the middle of the frame, but try off-center placement. Exploit other elements in the your view, like plants, twigs or color areas, such as shadows or parts of the sky. See sample here.
Technically, the good news is that you don't need a dedicated macro lens for this type of photography, in fact, a good zoom lens with macro capabilities is better suited, because you can place yourself at a comfortable distance from the insects without scaring them away.