How do I create editable layer on top of basemap layer in ArcMap?
I would recommend starting with the tutorials, specifically the editing tutorial.
I believe you can download the tutorial data from your My Esri page under My Organizations - Products - Downloads - ArcGIS for Desktop - View Downloads
I agree with Jake that you should check out the ESRI tutorials. Whenever I need to do something new in ArcGIS, I check to see if a tutorial is available.
In a nutshell, this is how to create a new layer:
I create new layers using ArcCatalog.
1. Navigate to the existing geodatabase that you wish to add the layer to or use your default geodatabase.
2. Right click the geodatabase and select new> feature class.
3. This opens a GUI that guides you through the steps to create the layer.
*I generally import my coordinate system from an existing map (click the drop down menu beside the globe at the top)
* make sure you add the fields that you will be editing
4. Open ArcMap and add the layer to your map.
5. Right click the layer in the Table of Contents and select Edit Features> Start Editing.
I hope that helps.
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