From the xCenta Dashboard, click on the Documents icon in the Modules section.
A new page will appear. Select the relevant folder, find the document you wish to check in and click the 
A pop up will appear, click Yes, No or Cancel.
If you clicked Yes or No, you will then be directed to a new pop up about updating the document, fill in the relevant fields.
Version Number is optional, you may want to use it, for example, if you want to upload an updated version of something, the version number will let people know this is a newer version. the old version will then be archived.
Then click Next.
The next stage of the pop up will then appear, fill in the relevant fields and click Next.
Next you can now add more document tags at your own accord. Finally if you are happy click Finish.
When you have clicked finish you will be taken to the screen below and it will show that a document has been checked out and then back in again.
If you are unable to follow these instructions, you may not have the required user permissions. Please contact your Site Administrator.