Added a workaround for a missing tree command.

1-Setup.md

@@ -111,4 +111,27 @@ $ tree ${EPICS_DIR}
 ```
 </details>
 
+If the **tree** command doesn't exist, there is a workaround:
+<details>
+<summary>workaround</summary>
+
+The **find** command can be used to show all directories inside a specific directory. 
+
+bash
+```bash
+$ tree() { find $1 -type d | grep -v git; }
+```
+
+tcsh
+```csh
+$ alias tree "find \!* -type d | grep -v git"
+```
+
+Once the bash function or tcsh alias is defined, the tree command can be rerun:
+```bash
+$ tree ${EPICS_DIR}
+```
+
+</details>
+
 ## [2 Deploy a new IOC](2-IOC-deployment.md)