You can't do a marketing plan without getting many people involved. No matter what your size, get feedback from all parts of your company: finance, manufacturing, personnel, supply and so on--in addition to marketing itself. This is especially important because it will take all aspects of your company to make your marketing plan work. Your key people can provide realistic input on what's achievable and how your goals can be reached, and they can share any insights they have on any potential, as-yet-unrealized marketing opportunities, adding another dimension to your plan. If you're essentially a one-person management operation, you'll have to wear all your hats at one time--but at least the meetings will be short!
Chart to success: We all know that plans are imperfect things. How can you possibly know what's going to happen 12 months or five years from now? Isn't putting together a marketing plan an exercise in futility . . . a waste of time better spent meeting with customers or fine-tuning production? Yes, possibly but only in the narrowest sense. If you don't plan, you're doomed, and an inaccurate plan is far better than no plan at all. To stay with our sea captain analogy, it's better to be 5 or even 10 degrees off your destination port than to have no destination in mind at all. The point of sailing, after all, is to get somewhere, and without a marketing plan, you'll wander the seas aimlessly, sometimes finding dry land but more often than not floundering in a vast ocean. Sea captains without a chart are rarely remembered for discovering anything but the ocean floor.