Stick to a soothing color scheme. Shades of white and muted earth tones are best. Stay away from bright colors and distracting patterns. You don't want anything to take away from the spa experience.
Decorate the walls with framed artwork that matches your chosen color palette. Cover the windows with sheer shades or coordinating curtains to let a soft glow of light into the room. Use low-watt bulbs in light fixtures or install a dimmer switch so you can control the amount of light.
Neatly fold or roll plush towels and stack them in a convenient shelf or basket. Place comfortable, coordinating bath mats in front of the sink and bathtub.
Place plants in ceramic pots around the room to bring the outdoors into the space. Fill bowls or glass candleholders with pebbles and place tea lights or votive candles on top for ambiance.
Keep the room meticulously clean and free of clutter. Stow products in drawers or cabinets. Keep essentials in glass or ceramic jars with lids. Keep the bathroom fully stocked with toilet paper, soaps, bath beads, scented oils and facial supplies for when you want to pamper yourself or your guests.