Better screw holes
When you have to use screws that will be removed often drill the holes for the screws large enough to allow you to insert a small piece of Sullivan Gold-N-Rod glue the rod in the hole. The screws can then be removed and reinserted with out weakening the wood.
Mark Hinges
When using CA hinges use a marker to draw a black line across the middle of the hinge. This way you can tell if the hinge is being pushed into the wing when you put on the aileron. I have had some hinges do this and end up with a sixteenth of an inch in the aileron and the rest in the wing, not very strong. If you can't keep the hinge from being pushed into the wing stick a pin through the middle of the hinge it will not weaken the hinge at all
Easier plastic bolting
After you cut a plastic wing bolt stick it in one of those cheep plastic pencil sharpeners and give it a beveled tip this makes it much easier to insert the bolt and cleans up the start threads
Better holes
IF you have to drill a hole in thin balsa do not try to use a common wood drill it will usually leave a ragged hole that is the wrong size. Go to the hobby store and get a piece of thin wall brass tubing the same outside diameter as the hole you want to drill. Mount the tubing in an electric drill (preferably a drill press) then hold a piece of sand paper or a file against the end while turning to sharpen it. Use this to drill your holes it will cut perfect holes. After cutting several holes you may have to push out the wood that collects inside the tube with a stiff wire. If you can find a drill the same size as the inside of the tube stick in in the top part so the drill chuck does not crush the tube. Also watch that the tube does not flare out at the bottom and change the size of the hole
Dust collector
Next time your wife yells about the balsa dust from sanding steal one of her large fluffy bath towels and use it to sand on. It not only protects the airplane from dings, but it will trap a huge amount of dust. When done sanding fold it carefully then take it outside and shake it out.
Note: see disclaimer above, I am not responsible for what happens when your wife catches you doing this