Model plane enthusiasts have been doping on nylon for donkeys years now. The method became less popular with the advent of iron on coverings such as Monokote, Solarfilm and Solartex etc. but has always hung on.

Provided the job is tackled in a planned out manner, covering with nylon and dope is quite easy. It takes longer than some newer methods but the finished model will be extremely tough and durable (won't sag in the sun neither).
Start off by sealing your wooden airframe. Use dope for this preferably with talc added or premixed cellulose sanding sealer. You will raise the grain of the wood with the sealing coat, sand it down good and smooth in preparation for the nylon application.
Cut out your panels a bit oversize, leave plenty extra at the wingtips and any awkward places. I always apply nylon while wet (after a bath or a walk in the rain!). Seriously though it's far easier to get good results with wet nylon. Put the nylon panel under the tap, get it plenty wet then squeeze out as much water as you can. Open the panel out and shake it, now place it over the airframe and apply thinned dope to the edges to hold it in place. If there is not much wood to grab the nylon at the edges feel free to pin the nylon to the airframe and use full strength dope, pull the edges of the nylon to get rid of wrinkles and slackness while adding dope to the edges only (Dont rely on the shrinking power of the dope to pull out massive wrinkles, get it looking good and even).
The panel can now be allowed to dry, the dope will dry first grabbing the nylon to the airframe, then the water will evaporate from the nylon and it will gently shrink, making your good job look even better! The water shrinking is mild when compared to the later doping but still take care to avoid warps on light structures (pin em flat).
Generally it's best to cover the underside of the wings followed by the upper surface, this allows the overlap to be less visible. Similarly cover the bottom of the fuselage, then the sides, and lastly the top.
When all the panels are in place, go over all the overlaps and panel edges with more dope to make sure they are all stuck down well and truely, this is more important for open frameworks.

This model aircraft of my own design is mostly covered in nylon. The booms are tissue covered, and the control surfaces are in the process of being covered in aluminium fibafilm.
The model has been sprayed with gold and red enamel and awaits a coat of fuel proofer (probably be Tufcote gloss).

Materials needed for this covering method are as follows

Nylon of suitable weight and colour

Can of cellulose shrinking dope and associated thinners

Talc powder or sanding sealer

Small amount of castor oil or can of banana oil

Modelling pins

Brush

Scissors (good ones)

Scalpel (very good one)

Newspapers or similar for your work area

Cutting board

Plain paper for templates

Fresh air and plenty of it

Allow the airframe to dry out then begin the general doping. I use 50/50 shrinking dope and cellulose thinners. Brush this on avoiding as much as possible the already doped edges on an open frame (no worrys for mostly sheeted surfaces, just slap it on).
If the airframe is rigid and warp resistant then you may be OK just doping on both sides and allowing the nylon to shrink both together. On anything less than really rigid pin the panel down as soon as possible while the dope shrinks to avoid warps (best left pinned for a couple of days if possible, dont't let it stick to the surface!).
Continue with as many coats as you see fit, I generally tidy up the model as I'm working at this point, cutting off loose ends and surplus material then doping down as needed. The weave will gradually fill as more coats of dope are applied. A good option for the later coats is banana oil intead of dope or just mix in a very small amount of caster oil as a plasticiser (ordinary dope becomes brittle with age). Non shrinking dope can be used when the covering is taught.
That's mostly it, a few things to watch out for are spars below the surface on open frameworks, the nylon can sag when doped and stick itself to parts it ain't supposed to. When covering an aircraft in nylon I often make use of tissue for certain areas (generally sheeted areas), this I apply dry and dope it on working from the middle outwards, tissue can also be applied over the nylon to tidy up some areas of an airframe.
When the model is fully dry (stopped stinking the shed out) paint can be applied. Many paints will work but they are best sprayed on in light coats, a heavy brushed on cellulose finish over an open framework is likely to spoil your whole day.

I love the smell of aircraft dope in the morning.

The tail of the aircraft showing where the nylon stuck a bit to a spar.

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