Have a look at Ryan Cleckner on YouTube.
https://youtu.be/EF2wYn3nj4E
This video is one of the best I've seen. Essentially bore sight it at 25yrds, Take a shot and get it on paper. Move back to 100 and fine tune. A folding chair/table is great or a back pack on the ground. As always just know what's behind your target.