Over the years,I've used most methods, latex,sorgum and epoxy. By far the easiest and the best is the method originally used by Bill Evans of Bishop, California. Simitar Hobbies.This is double sided tape about 2" wide with backing. You completely cover the wings in strips. remove the backing and all that is left is a thin layer of glue. It sticks great and adds very little weight,clean and east to use and does not require weight as it sticks instantly.. One roll of the tape would cover about 2 normal size wings.
I am not sure, but last time I heard Bill Evans was not well and may have left us and Simitar may no longer be in business. The original product was of US manufacture but has since been replaced by a Japanese product
If Simitar no longer sells the product, it is available here in Australia and I can get you in contact with the supplier.