Usually, you will want to choose an extension hair that matches or blends with your own texture. If you wear your hair mostly straight, buy straight. Straight hair can be scrunch-dried to produce a soft wave.
Do not that waves and curls loosen and fall with washing. If you need an actual curl to the extension hair, or more wave than you see in the photo above (whether yours is natural or from a perm) choose the curly extension hair in the ManeMaxx® Extension Hair but be sure to follow the pre-application steps for preparing wavy or curly hair for application.