First, verify the status of the uploaded VAT data before e-filing. To e-file VAT data, follow the steps below : 

Step 1. Click on the hamburger  menu of MTDVAT.
Step 2.Now open the hamburger menu and click on the sub menu option "Key In MTDVAT Data".
Step 3. This will take you to the page with the 'Key In MTDVAT Data' button, click on it.
Step 4. Once you've done the third step, you'll be taken to a page with your VAT info. Just click 'Confirm' on it to keep going. 
Step 5. Once you’ve confirmed the VAT information, you’ll also want to make sure that the information you’ve given the trader is accurate.
Step 6. Once you have confirmed the assigned trader information, select the client you need to e-file and click the e-file option..
Step 7. Once you have selected your client and confirmed your e-file choice, enter your password and select 'click' on the 'e-file' option.. 
Step 8. Once, clicked e-file, it will show the result immediately, or in few minutes as "Successfull".

RoadMap On How to E-File the Uploaded MTDVAT Data:  Click on the hamburger  menu of MTDVAT -> Select "Key In MTDVAT Data" -> Confirm your "Vat Info" -> Select the Client you want to E- File -> Enter you PassCode -> CLick on E-File .

Here's a video on how to e-file the uploaded MTDVAT Data: