How do I revert to an older version of iOS?

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Tags

1. #which
2. #version
3. #extension
4. #previous
5. #restore
6. #select
7. #window
8. #press
9. #click
10. #software
11. #choose
12. #folder
13. #right
14. #shift
15. #bottom
16. #iphone
17. #accessed
18. #updates
19. #button