Add instructions, TODOs, and public availability note

Signed-off-by: Angela Maio <angela.c.maio.civ@mail.mil>

docs/CONTRIBUTING.md

@@ -3,10 +3,13 @@
 All SubT Challenge competitors are welcome to contribute links to their open-source software, hardware, and datasets here. All contributions must include:
 
 1. A link to the open repository or dataset
-1. A brief (< N character) description of the resource, especially what makes the resource unique/novel 
+1. A brief (< N character) description of the resource, especially what makes the resource unique/novel *TODO: Select a word/character limit*
 1. Name of the SubT Challenge team who developed the resource
 1. Tags for the relevant event or subdomain
 
+Contributions must be open source and publicly available. 
+Licensing information is recommended to be included at the resource link, but no specific licenses are required for contributions to be included here.
+
 Please add the resource under the most appropriate technology area in the following categories:
 
 * [Mobility](1-Mobility.md)
@@ -15,6 +18,15 @@ Please add the resource under the most appropriate technology area in the follow
 * [Networking](4-Networking.md)
 * [Simulation](5-Simulation.md)
 
+Follow these steps to add your resources to this repository:
+
+1. Clone this repository locally using `git clone <repository_url>`
+1. Create a new branch that includes your team's name with `git checkout -b <new_branch_name>`
+1. Edit the files locally using markdown formatting. Add and commit your changes with `git add <file>` and `git commit -m "<commit msg>"`
+1. Submit a [pull request](TODO) to the `main` branch *TODO: Update link to public repo PR page*
+1. Look out for pull request activity and please respond promptly to reviewer requests.
+1. Your pull request will be merged and your resource links will be available on the `main` branch! 
+
 ## Examples
 
 Example contributions are provided in [Simulation](/Simulation.md) and [Autonomy](/Autonomy.md).