Hi!
It's very easy!
You brush on dope (Cellulose laquer) on the balsa stringers several times and let it dry between times.Then you place the wett issue on the stringer frame! Do not forget to spray water on the paper before you place it on top of the wing /fuselage!!! You fasten the tissue to the stringers by brushinng aceton on the wet tissue surface. The aceton will get through the wet paper and will loosen up the underlaying dope on the stringers which will let the paper adhere to the balsa stringers. Let it dry for some hours untill the tissue surface is tight and dry. Then brush on dope on the whole surface. The dope will now shrink the papper even more...Apply as many layers of dope you like untill it's ready for paint.
Ofcourse you sand it and use a "tack-rag"before you apply any paint!