Just exactly what does this mean ? What is a droplet ?
a droplet is a virtual machine from Digital Ocean. The guide on protoshares.com shows one way to mine and it happens to be on the cloud. If this is your first time mining, then I suggest you start mining locally first to learn about the process and be comfortable with it before spending more money on it.
There are other "pools" you can join to mine with your processor (CPU). It's a bit slow until you get to 1 PTS but you will learn alot along the way.