A good set of plans can eliminate a lot of trial and error on the path to a finished project.
Customizing a wooden outer box for this metal interior required neither plans nor measurements, only part-to-part marking.

A good set of plans can eliminate a lot of trial and error on the path to a finished project. Followed carefully, step-by-step instructions and detailed illustrations will result in a project identical to the piece pictured in the plan. But what happens when that picture doesn't match the idea in your head (or the size of your living room)? Here are a few tips to guide you on the path toward designing and building your own unique project.

Start with the critical dimensions

Growing up, I built a lot of custom built-in cabinets with my father. Fixed points, such as walls or doorways, constrained the dimensions of the cabinets, so a few measurements gave us the basic outside dimensions of the project. From there, it was a matter of designing the remainder of the project from the outside in. Alternatively, the size of your television or components dictate the critical dimensions of an entertainment center, requiring you to dimension from the inside out.

Take a cue from standards

Even if your prospective project does not have ready-made critical dimensions, you can skip some guesswork by using tried-and-true furniture standards. A quick search online will bring up standard heights, depths, and widths of chairs, below, tables, and cabinets. These standards have been developed over generations and provide a good starting point to fit the average-size person. Once you know the standards, a quick mock-up tells you if an adjustment needs to be made to fit you or the end user.

Are you shorter or taller than average? These traditional chair dimensions provide a good design starting point. Adjust them as needed to suit you.

Make a nod to style

Beyond the fit and function, be mindful of the form. Much furniture can be categorized into a handful of design styles—Arts and Crafts, Shaker, and Queen Anne, to name a few—or has been heavily influenced by them. Within each style, trademark elements create aesthetically pleasing and functional forms. As you're getting started with custom designs, borrow from these well-vetted styles to ensure a piece that will be enjoyed for years to come.

Choosing to design in an established style, such as Arts and Crafts, helps you focus the form of your project, making the task less overwhelming.

Toss out your tape measure 

This may sound like an extreme action, but after establishing the basic dimensions of the project, precisely targeting a tickmark on your tape is not as critical as ensuring that each component fits well. With a case built, I often mark the length of a component, such as a shelf, directly against the case instead of relying on the intermediary of a tape. This minimizes the opportunities for error and takes no more time.

For built-in cabinets, a story stick makes a great way to directly transfer wall dimensions from the installation location to the shop.