Cryptography isn't like that, it doesn't boil down to 10 simple steps. If you want ten, it's happening at higher level
1. Never invent your own primitives. Only professional cryptographers do that in algorithm competitions like AES, SHA-3, or PHC.
2. For interoperability, use BoringSSL, LibreSSL etc. Hire developer who knows how to do this. Or, hire a professional applied cryptographer to build TLS from low level primitives if you have a reason it's needed.
5. Have the implementation audited by professionals. E.g. Kudelski Security or NCC Group.
6. Have a bug bounty program that compensates well, and that allows disclosure of the attack.
7. If you're in a market where the competition has open source clients, you should have an open source client too, so that anyone can verify your cryptography is correctly implemented.
8. Keep anything that's WIP, under "research prototype, do not use in production" banner. That's not a cone of shame. If Dan Boneh can do it (https://crypto.stanford.edu/balloon/), so can you.
9. Realize that 90% of the work in cryptography is key management. Use OS keyring when possible.
So yeah, sorry, no "Use XChaCha20-Poly1305 or AES-GCM only", or "Use X25519/ed25519" or "remember to hash the X25519 shared secret". That's too in-depth for a ten point list. At that level, it's more of a top-ten book list.
1. Never invent your own primitives. Only professional cryptographers do that in algorithm competitions like AES, SHA-3, or PHC.
2. For interoperability, use BoringSSL, LibreSSL etc. Hire developer who knows how to do this. Or, hire a professional applied cryptographer to build TLS from low level primitives if you have a reason it's needed.
3. For closed ecosystems, use opinionated, misuse-resistant, high level libraries like libsodium, or libraries binding to it https://libsodium.gitbook.io/doc/bindings_for_other_language...
4. Use kernel CSPRNG to generate all secrets.
5. Have the implementation audited by professionals. E.g. Kudelski Security or NCC Group.
6. Have a bug bounty program that compensates well, and that allows disclosure of the attack.
7. If you're in a market where the competition has open source clients, you should have an open source client too, so that anyone can verify your cryptography is correctly implemented.
8. Keep anything that's WIP, under "research prototype, do not use in production" banner. That's not a cone of shame. If Dan Boneh can do it (https://crypto.stanford.edu/balloon/), so can you.
9. Realize that 90% of the work in cryptography is key management. Use OS keyring when possible.
10. Deploy end-to-end encryption everywhere you can. Data is a toxic asset. https://www.schneier.com/blog/archives/2016/03/data_is_a_tox...
So yeah, sorry, no "Use XChaCha20-Poly1305 or AES-GCM only", or "Use X25519/ed25519" or "remember to hash the X25519 shared secret". That's too in-depth for a ten point list. At that level, it's more of a top-ten book list.