I usually put on some music..maybe ENYA (be still my heart ) or whatever and just have a go at it. Swirl the brush tip in water and wipe the tip on a paper towel from time to time as you go along. Makes brushing the glue easier and without much excess glue buildup.

Another suggestion if I may: On your wing you might want to add some 1/16" sheet balsa shear webbing (vertical grain) to the back of the main spars and carry this outward to the wingtips. I know it can be a pain to do this but the strength factor on your wing will be greatly enhanced. I'd do this on the rear spars at least halfway out towards to tip, too.

Soft landings.

Joe