Open Service Studio and access the Connect to Environment dialog. This can
be done in two ways.
a) If you are not logged in to any environment, click on Connect to
Environment 

b) Under the Platform tab and then under the Personal Environment tab the
environment address (or Server Address) can be found 

c) Back in Service Studio, use that Environment and login with your
OutSystems community email (username) and password. 

Install the Contacts application
Open and publish the REST Contacts - GET.oap in your personal environment. The oap
file can be found in the Resources folder.
1) In the Applications, open the Environment menu and select Open Files..
2) In the Open dialog, change the File Type dropdown option to OutSystems
Application Pack (*.oap) and then open the REST Contacts - GET.oap.
3) Click Proceed when asked.
4) Wait for the installation to complete and then proceed.