Create and sign certs with OpenSSL 

In this video, I talk about how to create and sign certs with OpenSSL (and convert them to PFX for Windows). This came out of my complete inability to ever remember how to do any of this, so I created a cheat sheet and then recorded this video off of it.
Cheat sheet below:
Self-signed
Generate a new private key:
openssl genrsa -out blah.key 4096
Create a self-signed cert from the private key:
openssl req -x509 -key blah.key -out blah.pub -days 365
Verify the certificate:
openssl x509 -noout -text -in blah.pub
Do all of the above in a single command:
openssl req -x509 -newkey rsa:4096 -keyout ca.key -out ca.crt -days 365 -nodes
Convert to pfx:
openssl pkcs12 -export -in ca.crt -inkey ca.key -out ca.pfx
Using a key to sign another:
Generate a new private key
Create a CSR from the private key:
openssl req -new -key blah.key -out signable.csr
Do both in the same step:
openssl req -newkey rsa:4096 -out signable.csr -keyout signable.key -nodes
Sign the CSR with the CA cert:
openssl x509 -req -in signable.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out signable.crt -days 365
Export as PFX:
openssl pkcs12 -export -in signable.crt -inkey signable.key -out signable.pfx
For more on me: brianparks.me