Ephemeral-ness in as much of your life as possible seems to me to be a much overlooked aspect of Privacy, Security and Anonymity.
The more you use persistent storage, firmware, hardware and software, repeat the same patterns in your communications and actions, rely on the same techniques, apps, emails or social media accounts etc.
The weaker your security model.
Yet we are creatures of habit and we don’t want to make it difficult for our friends, work, etc.. To contact us. Changing emails every few weeks, or phone-numbers etc.. Is not really a viable option for most of us. So what is the solution?
We can take some steps initially.
IP and mac-randomization, Using OS’s in a Live or ephemeral mode, (like TAILS or Kicksecure Live Mode), using cash, wiping phones, disks, and devices as often as possible of all data, storing emails online at the absolute bare minimum, staying away from cloud services, minimizing contracts and other entanglements etc.
Knowing that everything online leaves a trace and that trace is a threat changes things dramatically when you realize its full significance.
For instance know that every crypto transaction is stored indefinitely on the block chain. (That one purchase on Silk road etc.. Is there over your head forever!)
All credit cards, even anon ones are building a profile on its user.
All contracts, with phone, ISPs, landlords etc..
Trying to live Ephemerally is an art in itself, and an interesting philosophical experiment. Not out of paranoia but curiosity, to really see our unnecessary entanglements and really feel free.