To start off, it is important to become accustomed to the development environment we will be working in. As of writing at the start of 2019, the only supported development environment is the Plutus Playground: https://prod.playground.plutus.iohkdev.io/
Simply hop on over, and you will be greeted with 4 example smart contracts, with one pre-loaded. Writing and working with smart contracts in the Plutus Playground works as follow:
I recommend taking at least 5-10 minutes with the predefined examples to get use to the whole process before we continue.