1. In the editor, you can click on the Share option on the left top corner.

2. From there, you can choose to Check in to / Check out from the spreadsheet. Checking out from a spreadsheet will make it Read-Only for all collaborators.

3. Alternatively, in the Zoho Sheet listing page, you can select and right click on the spreadsheet you want to check out from.

4. From the menu that appears, choose Check in/ Check out.