Navigate to the item you want to attach files to and click the Attachments tab.
On the Attachments tab, click Upload to show the Open dialog.
In the Open dialog, select the files to upload and click Open.
The Upload dialog opens.

Optional: In the Upload dialog, enter descriptions for the files you are uploading.
Optional: If you want to store a file in a folder, select an existing folder or create a new one from the Upload to box.
Click Upload.
The upload progress is shown at the top of the screen.
If an item contains folders, you can move attachments to them.