Add in technique scripts

Add instructions to install the technique scripts, which are often useful, but were not actually listed in this documentation

Author: KathrynBaker

doc/overview/First-Time-Build.md

@@ -177,6 +177,14 @@ git checkout <NDXXXX>
 The developer branch has been created to store useful configurations that may be shared amongst all developers.
 ```
 
+## Installing technique scripts
+Some sets of instruments use shared scripts based on the techniques they employ, so installing these scripts would be helpful. Note that these are stored in a repo in an organisation that includes more of the scientists than our typical organisation.
+If the `C:\Instrument\Settings\scripts` directory already exists, cd into it and do a `git pull` on master. Else run the following command from a Git-enabled command prompt (or modify target to run with Git Bash):
+
+```
+git clone https://github.com/ISISNeutronMuon/InstrumentScripts.git C:/Instrument/Settings/scripts
+```
+
 ## Setting up a calibrations directory
 
 If the `C:\Instrument\Settings\config\common` directory already exists, cd into it and do a `git pull` on master. Else run the following command from a Git-enabled command prompt (or modify target to run with Git Bash):
@@ -271,4 +279,4 @@ XAR is the runtime that but for testing you will need the full setup which is th
 ```
 
 ### Install WiX toolset (We use version 3 and not the latest one - only install if required)
-Download and install latest stable version from https://wixtoolset.org/docs/wix3/
+Download and install latest stable version from https://wixtoolset.org/docs/wix3/