Installing SSL is very easy. All you need to do is be in your domain group, click "Actions" and then "Add SSL Certificate" in the SSL certificate section. There you can install Let's Encrypt (free SSL certificate) or a custom SSL certificate.
If you wish to install a custom SSL certificate, you can generate a CSR if you don't have one already.
SSL installer runs in 15 minute intervals and your domain's health status must be "Healthy" before you can install a SSL certificate.
If you install an SSL certificate when your domain's health is in the "Attention" or "Error" state, then SSL will not be installed before your domain's health turns to "Healthy." If your domain's status is not "Healthy," click on the status to see what's wrong. Your root domain and www subdomain must point to the IP address where you assigned your root domain. E.g.:
priorityprospect.com - 10.0.0.1
www.priorityprospect.com - 10.0.0.1
Also, make sure your domain doesn't have AAAA (IPv6) record set up for your domain. Let's Encrypt will use the AAAA instead, and the SSL installation will fail.
If you see "Not Secure" on your address bar after installing the SSL certificate, then it means your website is loading static assets over the HTTP connection. You must ensure all assets load over HTTPS, and this notice will disappear.
If you install SSL to a domain that you host with Cloudflare, make sure you have set up the SSL certificate and turned on the "Full" and not the "Full (strict)" SSL setting in Cloudflare. It's required to prevent infinite redirect and the 525 error.