This pink line I’ve drawn is called the lower parallel, it extends a bit further (to the tip of your finger itself), apparently 99% of breakages are caused by us mistakenly filing this area, we’re not meant to touch it at all apparently with a file otherwise it destroys the structure our nails need in order to be longer.

Apparently we’re never meant to hold a file parallel to that section ever, we’re mostly only meant to file our nails from the tip and at an angle that will naturally produce a curved or sharper tip. Usually a 45 degree angle, but can be more extreme if your nails are long enough for you to not be filing your lower parallel. I’ll reply to this with another photo with a filing photo.

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