Step 0: Cutting the parts
The wooden parts are designed to be cut from 4mm plywood. You can choose the fabric for the wings as you like, it just should be a bit elastic. I took a woven fabric with a rougher structure to match the old look.
Step 1: The wings
When assembling I would rocommend starting with the wings, which are assembled as seen in the picture below. It works best when you place the two spars on a flat surface (i.e. a table) and then place the ribs so that their ends extend beyond the edge. This is because they go further down. Check the ribs before glueing, they are all different!
Step 2: The wing centerpiece
This one is easy, just glue the 4 parts together like in the picture below.
Step 3: The gondola
The gondola is also easy, just take the 2 bowed pieces and glue the 4 floor boards onto them. The cuts in the boards ensure correct spacing.
Step 4: The fuselage
Take the long fuselage piece and get it in the gondola like in the picture. Glue it in and attach the rear wing to it.
Step 5: Attach the wing connector
I guess the picture gives it away anyway, just glue it to the rest of the glider.
Step 6: Wings
Glue the wings into the wing connector and put some kind of support unter them to make sure they are on the same height. When the glue has dried you can put the fabric on. I would rocommend starting with glueing them to the wing connector first and then work your way out by glueing it stepwise to the wing. The wing pattern was made by trial and error, so don't wonder if you have excessive fabric, you can cut that off.
Step 7: The wiring
If you like you can also add wiring as you can see in the photos. When you don't want to fiddle around with that, don't worry the glider works well without it.