Once you have all your materials securely attached to your wall it is time to grout. Grouting is the messiest part of creating a mosaic. Before you begin, you’ll want to give some thought to color. The darker the color of the grout, the more it will recede allowing your objects to pop. But if the negative space created by the grout is an integral part of your design, you may want to consider making it a color – keeping in mind how it will relate to the color of the objects.
Sanded grout should always be used if you have more than 1/4″ thickness between your objects. Mix the dry grout with water to the consistency of oatmeal. If it’s too soupy it will run down your wall and take forever to dry. Too thick and it will crumble and dry too quickly. You can always add water to your mixture as you use it.
I don’t have a surefire easy method for grouting around various thicknesses of objects. It is slow and messy. Check out the various pottery utensils available in art supply stores. You can use all sorts of tools to push the grout between the objects – small spatulas, knives, spoons, and your fingers. Experiment to find what works best for you.
I applied the grout in approximately a 3′ by 3′ section at a time. It’s important to start cleaning away the excess grout before it becomes too dry. Cleaning up the grout is tedious. If you start when it’s too wet you will take too much off and have to reapply. Have one clean water bucket and a dirty water bucket to go back and forth with sponges. I used a stiff paint brush to scratch away a lot of the excess grout before resorting to wet sponges. Carefully smooth the grout around each of the objects leaving enough grout to keep each piece secure.
Beautiful mosaics are about the overall design, and beautiful workmanship is always evident in the application of the grout.