Recently, I took a woodworking class at my grad school where we had to design, draft, and build a piece of furniture. I went with a secretary desk because it A) incorporates a lot of different joinery and problem-solving, making it perfect to build as an intermediate project, and B) is super-functional for my small grad-student apartment. This Instructable details the design process all the way to finishing construction; I'm still in the process of staining it, but I kind of love the raw wood look. Everything below is what I used for the sake of learning new techniques, but much of this build could be simplified down to using fewer tools.
Lumber of your choice (I chose poplar from Lowes, since it was the lowest cost while being a little better than pine for the amount of wood needed)
Step 1: Brainstorm Your Design
Since this was a project for my own use, I did some research to figure out what would be the most useful for me. After looking at a lot of secretary desks online, I decided that I would want a hutch that could function as a divided-up shelf, and have an area underneath that I could easily slide papers or my laptop under. Secondly, I could create a letter tray inside the hutch with wide but short dividers, but make the shelves like inserts so they could be removed as needed. And lastly, I wanted a large drawer in the base because what's a desk without a drawer?
Step 2: Drafting in AutoCAD
Once I determined the scale and rough design of the project, I used AutoCAD to draft and work out the specific joints and dimensions. When designing a piece of furniture, I found there was a lot of trial and error to work out the specifics in dimensions, joinery, and just the ultimate design - my final product looked pretty different from my initial idea. AutoCAD is a great way to work out the kinks of a design, though, before going too far and finding your initial design has some unforeseen issues.
Step 3: Making the Base
My instructors recommended that my base use mortise and tenon joints to make the strongest base possible, and because we had just invested in a mortising machine for future use. I cut the tenons into the side boards of the base by raising the blade to just the cut-off height around the tenon. My legs were laminated from a few sheets of poplar and clamped, and then cut on the table saw using a tapering jig to create a soft taper on two sides of each leg (you can also buy legs pre-cut like this). I then cut the mortises by cutting the square hole at each end of the mortise, and then slowly working my way across to cut the full grove. If you don't have access to a mortising machine, you can just as easily use a kreg jig to attach the pieces with pocket screws, or dowel them together instead.
Step 4: Biscuits! (Not the Flour Kind)
All of your flat table tops or side panels can be built from narrower boards by using the biscuit joiner. Using boards that are slightly longer and wider than needed for the final piece (in inch is plenty), I marked out the location of the biscuits on both of the boards being joined together, and then cut the pockets using the biscuit joiner. I glued the biscuits in, joined the boards together, and clamped to let dry. Once they were completely dry, I used the table saw to square up the edges and cut the boards to their final size.
Step 5: Cutting and Fitting the Hutch
For my two curved side pieces, I bound them together with painter's tape and then cut them on a band saw so that the pieces were as identical as I could manage. I sanded the edges on a bench sander and sanded with a palm sander to make the surfaces as flat as possible. Using a router, I cut two groves into the inside of each side to create a dado that the shelving could slip into, using a piece of scrap to ensure the dados were the right width (I found it helpful to attach a board to the side piece to act as a router guide). I cut biscuit holes into the back of the hutch sides to later join the sides and the back together, and then fitted the pieces together to mark and create dado cuts for the inner shelving. Once everything was cut, I tested the pieces together to make sure everything fit together smoothly.
Step 6: Fitting It All Together
This is the trickiest part, since with a piece with so many parts that fit together, there's generally a lot of fussing. As I go, I try to check the fit of the joints just to make sure the final assembly goes as smoothly as possible and to adjust cuts as needed. The trickiest part is the hutch - use the doweling jig to drill the holes into the underside of the hutch, and then use marker pins to line up the locations of the holes on the table top. There may be a bit of mallet-ing and fussing, but it will ensure that everything lines up well when you start to glue.
Step 7: Glue It Up
There is never too much glue in a piece of furniture - I started with the base, and added glue to the mortises so that glue spilled out when the tenon was fitted (also, wiped away any excess glue with a wet cloth to reduce the amount of chiseling away glue needed later). I clamped all of the base pieces and let them sit overnight until the glue was completely set. Once it dried, I attached the table top with screws (I preferred not to glue this, in case I ever needed to take the piece apart to transport it).
You can do the same with all of the joints in the hutch, keeping in mind to fit the hidden-dado shelves into place before fitting the hutch together. I fit the pieces together, clamped them, and then attached the hutch to the base with dowel pegs once the hutch sides were completely dry.
Step 8: Sand Like There's No Tomorrow
Fortunately, any imperfections in the the surfaces biscuited together or dings in the wood from working can be cleaned up with some sanding. Since there's a lot of surface area, I found that a palm sander worked best for me. Start at 60 grit to work out and major imperfections, and then shift up to around 220 grit. 320 will leave a really smooth and nice surface, but check what's recommended for any finish you're putting on the piece.
Step 9: Ta-Dah!
And that's that; my desk is still awaiting finish, but gel stains (like those made by General Finishes) are recommended for poplar since they will leave the most even color. Since poplar is not the highest quality wood, paint would also be appropriate. Happy woodworking!