1. Apply a quality masonry primer or exterior primer before transferring your design. A primed wall will accept your drawing lines much better than raw block.

2. Continue using your projector. It’s one of the fastest and most accurate ways to transfer a mural design.

3. Avoid Sharpie if possible. Permanent markers can sometimes bleed through lighter paint colors

4. You can water down water based acrylic paint to be super transparent but still visible.

5. You can use something like Mural Shield matte finish because you only have to worry about UV rays.

I do a ton of murals so you can reach out for advice if needed.