Use painted furniture. Limit the amount of wood-toned furniture you use, as wood surrounded by wood can be overwhelming. Among large furniture pieces, white-on-white, which emphasizes hues ranging from true white to deep beige, lends a cottage-like touch and serves as an unobtrusive backdrop that helps colorful accessories pop. Accent furniture pieces, such as chairs and occasional tables, painted in vintage blues, greens and soft yellows, balance the white to keep it feeling light but not feminine.
Add fabric for contrast. Create a layer of texture to your knotty pine interior with rugs, curtains and accent pillows and throws. Despite the knots in the pine and the grain of the leather, both surfaces are smooth and relatively sleek. Knobby, and even rough, textures provide a subtle contrast that makes your home more interesting by providing natural resting places for your eyes to pause as they sweep the room. Experiment with highly textured and rustic fabrics, such as wool and burlap, that suggest "lake home" rather than shout it.
Create personality with color and pattern. Use brighter, more vibrant colors for the summery feel that's a cornerstone of Scandinavian design, or keep the colors deeper and more muted in keeping with a style that tends more toward lodge. Patterns work with color to help set the tone of your rooms. Don't be afraid to mix them — large with small, in contrasting shapes but complementary colors — large florals with narrow stripes, for example, or bold stripes with small dots.
Add personality with accessories. Think of accessories as your rooms' jewelry — the finishing touches that bring the rest of the design together. They present a perfect opportunity to remind yourself and your guests that you're enjoying your lake home. Incorporate into your design pretty stones or sand collected from the shore of the lake; branches, if your home is in a woodsy area; treasures made by local artisans; and other artifacts of lakeside living.