Peel the paste gently from the board without stretching it*. Place it on the face right away. 

Since you didn’t use any corn flour the underside should be sticky. If the paste is not sticking to the head, you can steam the underside - it will make it sticky. Use a steamer or a pan with boiling water. Be careful not to burn yourself. Steam the underside for about 1 second. 

I don’t suggest using glue because glue marks might show through the thin paste. 

* If the paste feels stretchy, leave it to dry for a few minutes. Don’t leave it for too long though - if it’s too dry you won’t be able to stick it to the head properly.