fix: Update documentation (#160)

README.md

@@ -14,13 +14,17 @@ They can then be used in your application like any other `.svg`.
 
 ## ➕ Adding a new icon
 
+Prerequisites:
+- Node.js using the version in `.nvmrc`
+- Yarn
+
 To find and add a new icon:
 
 1. Search [Material Icons](https://material.io/resources/icons/) for the icon you need
 2. In Figma, use the Material Design Icons plugin to add the icon to a document. Export the icon as SVG
 3. Clone this repo (`git clone https://github.com/nulogy/nds-icons.git`)
-4. Rename the SVG to desired icon name (in camelCase)
-5. Place SVG in `assets/` folder
+4. Install dependencies by running `yarn`
+5. Place SVG in `assets/` folder with the desired icon name (in camelCase)
 6. run `yarn && yarn build` to make the icon available to use
 7. Commit the changes using a [conventional commits](https://www.conventionalcommits.org/en/v1.0.0/) message
 8. Submit PR