Sign in or create an account: If you have an account, sign in with your username and password. If you don't have an account, you will need to create one before you can upload a file.

Click on the "+" button: Once you are signed in, click on the "+" button located at the top of the page. This will open the upload file dialog box.

Select the file you want to upload: Click on the "Select file" button in the dialog box to select the file you want to upload from your computer.

Click on "Upload": After selecting the file you want to upload, click on the "Upload" button in the dialog box. The file will then begin to upload.

Wait for the file to upload: The time it takes to upload a file will depend on the size of the file and the speed of your internet connection. Be patient and wait for the upload to complete.

Check that the file has uploaded successfully: Once the file has finished uploading, it will appear under the "Add documents" heading in the home page. If the file does not appear, try uploading the file again.