This guide is pieced together from docs available at https://github.com/connextproject/indra
Lets say you want to deploy an Indra payment node to https://indra.example.com (we'll call this url $DOMAINNAME)
First step: get a server via AWS or DigitalOcean or whichever cloud provider is your favorite. For best results, use the most recent LTS version of Ubuntu. Note this new server's IP address (we'll call it $SERVER_IP). Make sure it's able to connect to the internet via ports 80, 443, 4222, and 4223 (no action required on DigitalOcean, Security Group config needs to be setup properly on AWS).
Set up DNS so that $DOMAINNAME points to this server's IP address.