If cost is a challenge you can do as I did and use salvaged materials.Using a laser level I installed upper and lower wood trim. before hand I placed used Masonite along wall as wainscot. This will help give me a smooth surface when I paint stripes.

Step 1:

Using Joint Compound (sheet rock mud/plaster), I spread generous amounts between the wood trim keeping the bottom of the plastered space heavier than the upper. You can experiment with using a fork to tease the plaster to ad texture, motion and drama.

Step 2:

I begin placing seashells and other curious sea-themed items in a poetic and pleasing pattern. adding bright colored glass beads and jewels will make it "POP" when you are finished.

Step 3:

Using my Gran-daughter's favorite Barbie... NOT!!! Using a salvaged barbie Doll I like to cut off hair with sissors and then reduce the remaining hair with a heat gun. I pose the Barbie in a way so she can become a swimming Mermaid and secure it with a staple gun.
Plaster is used to fill in the legs and give her the proper mermaid parts.

Step 4:

Liquid nail adhesive is used to make her flowing hair and fins.

Step 5:

Now I paint the whole surface with the base gold my Dear Wife selected.

Step 6:

Then while following the directions I brush on the crackle glaze on. After required time I paint over the glaze with the white paint.

Step 7:

After paint is good and dry I use a Dremel tool with a wire wheel to remove paint over items I want to shine through. ALWAYS WEAR SAFETY GLASSES WHEN USING THIS POWER TOOL.

Step 8:

Give the paint a couple of days to dry and then go over in selected spots with wood stain of your choice using a small brush. I like to use the stain as if I was shading objects in a still life painting. Before the stain gets to dry I spray a mist of window cleaner to disperse the stain and soften the edges of the dark areas. ALWAYS PROTECT UN INTENDED ARES WITH PLASTIC AND DROP CLOTHES.

Step 9:

I first measured out my stripes with a laser and light pencil marks.This process can work on semi-smooth surfaces.

Step 10:

Placing laser beam on each pencil mark and follow line with painters tape. While I was working on this I changed my mind and decided to gradually widen the paint areas as it moves across the wall. This I hope will ad drama. I then mixed painters calk with a small amount of water and I apply it along the tape edge. This prevents line leaking of paint at tape seal. A damp cloth or moist sponge is used to smooth out the calking. Next allow 20 min for calk to seal (not completely dry) or tape will not pull evenly.

Step 11:

Paint desired colors being careful not to over brush and mix colors.

Step 12:

Before paint drys gently pull tape upward and maintain control of tape so it will not slap against your painted wall and be sure you have a place to put the messy tape after it is removed so you don't have to scream for your wife to help!