To make the vases, first you will want to spray paint your letters and wood mounting board. I choose a watermelon pink for my letters and a tan for the board. Be sure to spray outdoors! Those fumes will get you!
I’ve heard of some people using an xacto knife to cut the top of the letters open. I did it a little different and had my hubby drill a few holes where I wanted them in the tops. That way the flowers stand up better.