How to use

1. Press F3 to open the info

2. Grab your Eye of Ender (or equivalent)

3. Throw it

4. center your reticle on where it hovers

5. Input your X coordinate into the "throw 1 X" box, your Z coordinate into the "Throw 1 Z" box, and your Rotation Angle into the "Throw 1 Angle" box. 

6. press "Suggest Second Throw Location" button and go to the coords provided

7. repeat steps 2-5 for Throw 2

8. press Calculate Location

Depending on how far you are, it might be about 100 blocks off the first time. get to a high elevation and try again when you get to the given location- if the eye goes down, you're there. Otherwise, start the process again from that location.