Go over aspects of the home you find especially appealing. Decide what you will refurbish and what you will replace. Plan to keep original wide baseboards, dining room columns or a brick fireplace facade, for example. Keep an old cast-iron tub and add new faucets. Redo existing hardwood floors but install new kitchen cabinets.
Plan the remodeling room by room. Start with the kitchen. Figure out appliances, cabinets and flooring that will make the kitchen look upscale. Make selections that harmonize with the 1930s feeling of the house, however. Possible appropriate choices would be white appliances, dark oak cabinets and tile flooring that resembles gray slate. Sketch each room to feature something original to the house. Keep bead-board paneling in the back entryway, for example.
Take care of plumbing and electrical upgrades. Run new wiring, water pipes and drain lines in kitchen and bath areas. Preserve old plaster walls, if possible, or redo them after tearing out walls to revamp plumbing and electricity. Figure out how to add more insulation in the attic and exterior walls.
Remodel the exterior and landscaping. Install new siding that looks vintage. Use colors that blend well with the neighborhood in neutral tones, such as light brown or cream colors. Add a border of landscaping around the perimeter of the house after removing old, overgrown bushes and plants.
Paint the interior, but make mostly superficial changes. Paint plastered walls a soft yellow with white trim for a light, crisp look. Or place pale taupe area rugs over the hardwood floors and add a brown sofa and chairs, oak beds and an oak dining table. Use light fixtures and lamps reminiscent of the 1930s.