Use this site:
https://www.webpagetest.org/
Then post the link here.
For more we would need to know your url.
There are a bunch of posts here for speeding up your site if you search. Make sure no cache headers is turned off and use your .htaccess to set up caching. Search around and you will find an htaccess file to help you. It is here and on Ozzmods site. There are a bunch of things you can do.
You may also have to tweak your server.
Feel free to contact me if you still need help.