Within in 5 minutes you can can create self signed certificate on linux machine. First you need to open console and execute following command. Before executing following command first check openssl utility is installed on your linux machine.
# openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout mysitename.key -out mysitename.crt
Then open your apache configuration file and put following code in that file.
NameVirtualHost *:443
#purabtech.in
ServerAdmin purabtech@gmail.com
DocumentRoot /home/purab/public_html/purabtech.in/
ServerName purabtech.in
<Directory "/home/purab/public_html/purabtech.in/">
Order Deny,Allow
Allow from all
AllowOverride All
ErrorLog logs/purabtech.in-error_log
CustomLog logs/purabtech.in-access_log combined
RewriteLog logs/purabtech.in-rewrite_log
SSLEngine on
SSLCertificateFile /home/purab/projects/purabtech.in/self-sign/mysitename.crt
SSLCertificateKeyFile /home/purab/projects/purabtech.in/self-sign/mysitename.key
SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown
CustomLog logs/ssl_request_log "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"
Additional:
For gettting pem certificate from ssl cert.
openssl x509 -in mysitename.crt -out mysitename.pem -outform PEM