Step 1
Mix two parts PVA glue with one part water in a bucket.
Step 2
Dip a paint roller into your mixture and allow it to absorb some of the PVA mix.
Step 3
Paint a coat of PVA glue mixture evenly on your applied mortar. Allow the mixture to dry. You know when PVA glue dries when it is no longer white.
Step 4
Wash your paint roller in a tub or bucket of water. Do this repeatedly, replacing the water with a new batch of clean water every time until no more glue mixture dilutes away from your roller.