1)After you cut the main wing parts out, bevel them as per this drawing.
2)Start with the 2 panels on one side and bevel then tape the outside of the joint while its laying flat.
3)Turn it over and add glue to the joint.
4)Weight the inside piece and prop up the outside tapered piece 4" to 5" off the table. That will give the proper angle. Brace it some way so it cant move while the glue cures. I use scraps of depron and some pins.
5)As the polyurethane glue cures, it will expand up out of the joint. Durring the first 1/2 hour or so you can run a popsicycle stick over the joint and scrape off the excess as it comes out. You will end up with a nice joint if you stay after it from the beginning. Wait too long and you'll have to sand it or try to cut it off.
Once the outer panels are done, you can do the center joint the same way. I put glue in the joint then flip it right side up and put braces at each end then let the glue cure. I dont bother scraping out the excess as it foams up because it will not show and its impossible to get to using this method anyway
You can pre cut the slots for rudder and motor mounts or do them afterwards.