First, cut three sides near the lid. Leave one to act as a hinge. Insert your items and add packaging material so it doesn’t rattle around.
Second, cut-off the cap so that the curvature matches the bottom’s uncut shape. 
Flip it over, and tape it so that it looks similar to the opposite end.
Now, simply wrap it with brown paper, as if you were creating a Christmas present for the post office. 
Thanks for reading.
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https://tetrahedroseph.bandcamp.com/album/patient-31-covid-19-p-o-s
https://tetrahedroseph.bandcamp.com/album/viral-covid-19-a-s-a-p
https://tetrahedroseph.bandcamp.com/album/hoard-covid-19-t-p