Once all the wash areas have been tidied up, the Dullcote can be applied. My preference is to use the aerosol can, but there is another method, which is to use it from the bottle. Whether it is applied by bristle brush or airbrush it will need thinning, which requires cellulose thinners. I am not a fan of cellulose for anything to do with weathering, because I consider it unnecessary in that context. The effect of the toluene in aerosol Dullcote can be minimised by applying it outside in the fresh air, and the far smaller quantity expelled by an thinned airbrush solution can be handled by a good spraybooth extractor. If all of this puts you off, then a good matt varnish will do just as well.
A good even coat is applied and left to dry. It is touch dry in about 15 minutes and, for my purposes with this model, the pigments can be applied straight afterwards.