Disabling the editing option in arcgis.com pop-ups?

First off, be aware that Chrome does not work reliably for this, you are more likely to have it work in Internet Explorer

• On the ArcGIS Online window, at the top you have a menu bar with Home, Gallery, Map, Scene Groups, Content, Organization... click Content
• In the list of your content that pops up, you can find your hosted Feature Layer. Click it to see it's properties. If you have a lot of content that you have updated you can use the filters at the left to narrow it down to layers
• Again you have a menu near the top, on a blue bar - Overview, Data, Visualization, Usage, Settings. Click on Settings.
• Halfway down the page under Feature Layer (hosted) there is an Editing section. Uncheck the checkbox that says Enable Editing.