Firstly you should create new “Keystore” to install SSL certificate on server. Follow below:
Run command (Java Runtime Environment (JRE) had been installed).
§ Give password that you will use. "Enter keystore password:”.
§ Write server adresss (like www.e-tugra.com.tr) as answer "What is your first and last name?"
§ Write organizational unit as answer "What is the name of your organizational unit?"
§ Write organization name (like E-Tuğra) as answer "What is the name of your organization?"
§ Write City or Locality as answer "What is the name of your City or Locality?".
§ Write State of Province as answer "What is the name of your State or Province?". It can be same previous answer.
§ Write two letter country code (like TR) "What is the two-letter country code for this unit?"
Finally, create your CSR file with below commands
§ $JAVA_HOME/bin/keytool -certreq -keystore /.keystore -alias tomcat -file mydomain.csr
Remember the filename that you choose and the location to which you save it. You will need to open this file as a text file and copy the entire body of it (including the Begin and End Certificate Request tags) into the online order process when prompted