add nvm, node, and npm instructions

README.md

@@ -10,4 +10,49 @@ A guide for working on projects with the Cognition in Collectives Lab
 
 ### GitHub
 
-## TODO
+## Setting up your computer
+
+To work on our projects from your computer, you will need to install & configure a few primary software services and tools. Some of these are graphical user interfaces (GUIs), while others are command line interaces (CLIs).
+
+### JavaScript environment
+
+We use [Node Version Manager (NVM)](https://github.com/nvm-sh/nvm) to consistently manage Node.js and its versions in our projects that use JavaScript. To install, paste the following command into your Terminal application and run
+
+```bash
+curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.5/install.sh | bash
+```
+
+This will install `nvm` as a CLI, which will allow you to install and use various releases of the Node.js software. The installation should also have updated some of your system files that enable use of the `nvm` CLI. To verify your installation, run
+
+```bash
+command -v nvm
+```
+
+which should output `nvm` if successful.
+
+#### Node
+
+Once NVM is installed, you're ready to setup your default version of Node.js for working on CiCL projects using JavaScript. Start by running
+
+```bash
+nvm install 18.18.2
+nvm alias default 18.18.2
+```
+
+Then, to check the Node.js version, run
+
+```bash
+node -v
+```
+
+which should output `v18.18.2`.
+
+#### Node Package Manager (NPM)
+
+Check the installation of Node Package Manager (NPM) that comes with Node.js and make sure it has the correct version by running
+
+```bash
+npm -v
+```
+
+which should output `v9.8.1` or higher.