Regarding the seed phrases. There are many methods of how to store it, I guess those could be easily googled.
For those who are not sure what I mean when I mention RAID5 analogy:
- Split the words into 3 chunks. In the case of 24 words: Chunk1 contains the first 8 words, Chunk2 the seconds 8 words, Chunk3 the last 8 words.
- Take 3 papers.
- On Paper1 write Chunk1 and Chunk2
- On Paper2 write Chunk1 and Chunk3
- On Paper3 write Chunk2 and Chunk3
- Store Paper1 at your place, Paper2 at your parents place, Paper3 at some other secure place
To be able to restore the phrase you will need papers from at least 2 locations. If one paper gets lost you will still have the other 2.
This can be extended further to something like RAID6 where we have 4 chunks and store 4 papers at 4 locations which allows us to lose 2 papers and still recover the phrase…