If you are not familiar with the OGC instances (WMS, WCS. WMTS, WFS), you can read the documentation here.
Open the tab, you are interested in below.
Do you want to develop an app based on Sentinel-2 data? We have released Sentinel Playground application under open-source license in order to ease the integration of Sentinel WMS services in end-user applications.
Creating WMS instance
Create a new WMS instance. There is no need to limit the area.
Resulting WMS is:
Adding new WMS store in Geolayer
Go to Data ‣ Stores
Add new store.
Go to Other data collections ‣ WMS.
Type Sentinel Hub WMS In the WMS Source name input field.
In the Capabilities URL field type http://services.sentinel-hub.com/ogc/wms/<KEY>=GetCapabilities
You can leave Username and password fields empty.
Publish layers from WMS
Click “Publish” right of NDVI layer.
In “Edit Layer” dialogue you can change the bounding boxes to reflect the farm bounding box (only Lat/lon bounding box) - this will limit visualisation to only selected area. No other changes are needed.
Publish other layers
Go to Data ‣ Layers.
Click “Add new resource”.
Select “Add layer from” “Sentinel Hub WMS”.
Publish other relevant layers in line with previous points.
Go to Data ‣ Layer Preview.
Geoserver caches the WMS configuration (Capabilities). Therefore it is recommended to finish configuration before adding it to the store. Some further hints on how to work around this are here: http://gis.stackexchange.com/questions/18065/how-do-i-make-geoserver-update-layers-and-stores.