Once the sides are joined, and the frame and stem is made, it’s time to bend the sides, and make this stack of wood look like a boat! I highly recommend a dry run of this step. It can prevent major nervousness. And a goof found without glue is infinitely easier to fix.  

On the floor or work surface first attach the stem to one of the bow ends with two or three drywall screws and ¼” ply pads.

Now line the sides of the frame up with the marks on your sides. Hold it with a couple of your dry wall screws with the ¼” plywood pads. You have a big “H” now.

Using a “Spanish windless” – loop of rope with a stick twisting it to tighten it, (Or what I prefer is a truckers hitch instead of the stick) bring the bow sides together and screw the other side of the stem.

I actually use a variation on the trucker's hitch. Any loop in the end of a line can be used like a block (pulley) which gives you mechanical advantage, or "purchase" as shippy folks say. For this bending after it's pulled up tight a simple overhand knot "in the bite" (half bow) will secure it, since we're not driving this rig down the highway. Here's a great animation of a "real" truckers hitch that works well for securing loads... like boats!  http://www.troop9.org/knots/trucker.htm  Great boy scout knot site!

Now attach one end of the transom to one side end with drywall screws.

Now use a Spanish windless to pull the sides into the transom. Temp fasten this with screws as well.

Step back and admire your handy work. Now does that look like a boat or what!! Better put it on low saw horses at this point if you've been working on the floor.

          Now check for alignment. Stretch a tight string from bow to center line on the transom. Make sure it passes through the center mark of the frame. Adjust as needed. (Meaning bang it around a little.) We'll test fit the bottom before gluing it up.

Here is Chuck's stitch and glue version with the sides bent test fitting the bottom.