First thing you need to create CSR(Certificate Signing Request), so log in to your server.

openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out DOMAINNAME.csr

Then you need to enter the information as needed.

Copy your DOMAINNAME.csr and paste it your your SSL registrar.

Then you have gotten to wait for your registrar to issue CPTs.

Once you have CPTs, you will need to add those file to your server. I usually put them at working directory under ssl (For example, /var/www/domains/

Configure your nginx ssl, usually it is located at /etc/nginx/sites-available/ or wherever your is but my server is ubuntu.

Add this

server {
        listen          80;
        return  301$request_uri;

server {
        listen 443 ssl;
        location /{
             root /var/www/domains/;
             index  index.html index.htm index.php;
             try_files $uri $uri/ /index.php?$query_string;

        ssl_certificate     /var/www/domains/;
        ssl_certificate_key /var/www/domains/;
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2;


Restart your webserver

sudo nginx -t && sudo service nginx reload

You are now having a secure server!