Creating a Private Key and Public Certificate

Use the following OpenSSL command to create your private key. The command creates a 1,024-bit RSA private key stored in the file private-key.pem.

openssl genrsa –out private-key.pem 1024

Use the following OpenSSL command to create your public certificate. Run the command from the same directory that you ran the previous command to generate your private key. You will be prompted to enter some basic information for inclusion in the certificate, such as your name. The command generates a public certificate stored in the file public-cert.pem.

openssl req –new –key private-key.pem –x509 –days 365 –out public-cert.pem

That's all

Source: http://goo.gl/Cd24F