Update readme with instructions to run locally

README.md

@@ -23,3 +23,26 @@ Issues: **https://github.com/hl7-be/patient-monitoring/issues**
 Kanban board: **https://github.com/hl7-be/patient-monitoring/projects/1**
 
 ---
+
+### Running locally
+
+1. Install Prerequisites
+   Before running a FHIR IG locally, ensure you have the necessary tools installed:
+
+a. Java
+FHIR tools like the IG Publisher require Java. Download and install Java.
+
+b. Node.js and npm
+Some IGs may use Node.js scripts. Download and install Node.js.
+
+c. FHIR IG Publisher
+The FHIR IG Publisher tool is essential for generating and validating IGs. Download the latest publisher.jar from [here](https://github.com/HL7/fhir-ig-publisher/releases).
+
+d. Jekyll (Optional)
+If your IG uses Jekyll for hosting and templating, install Jekyll. Ensure Ruby and Bundler are installed.
+
+Run Locally:
+
+```
+java -jar path/to/publisher.jar -ig ig.ini
+```