Setup nginx as proxy server for your node below script for your reference
server {
listen 443 default_server;
server_name your.domain.com;
ssl on;
ssl_certificate /usr/local/nginx/conf/server.pem;
ssl_certificate_key /usr/local/nginx/conf/server.key;
ssl_session_cache shared:SSL:10m;
location / {
proxy_pass http://localhost:8545; # my existing apache instance
proxy_set_header Host $host;
# re-write redirects to http as to https, example: /home
proxy_redirect http:// https://;
}}