Here are some printable graph papers.
The measurement is the length of one side. Point to point they are 2x that size, and flat to flat they are 1.732x the given size.
The measurement is the height of the apple (longest measurement). Point to point (in either direction) they are 0.7071x that size.
These graph paper patterns are licensed under the Creative Commons Attribution-NoDerivatives 4.0 International License. Under this license you may share and redistribute this material freely as long as you leave the attribution intact and do not modify or reuse it in other publications. For your own use, you can do whatever you like with them - colour them, cut them out, use them in classes, etc.