Start by turning your Ombraz around, so the front of the frame is facing away from you.
Pinch the nose-pad with your fingers and pull out while pushing the lens through (you will hear some popping sounds and this is normal, it’s just the lens unseating from the groove of the frame).
To install your new lens, start by turning the frame so the front is facing you. Line the upper nose of the lens into the frame seating it into the groove, work your thumbs around the frame popping the lens into place.
Last, take your thumbs and run them around the perimeter of the lenses to make sure they’re locked in.
If your frames are too stiff, warm them up (but not too much) with a hairdryer or a defroster.
Check out this quick how to replace your lenses tutorial video for more info!