Once you have your thin pieces roughed out, they need to be brought to their final thickness, and the obvious choice for this is to use a planer, if you have one, or visit your local cabinet shop and use their planer or wide belt sander. Or you can belt sand the pieces with a hand belt sander to approximate thickness, though this is not a reliable means of getting a consistent thickness. Using hand planes to thickness the stock gives you more control, as well as sore muscles, but all kidding aside if you have a penchant for planes.
