Apply with a big paint brush
squeegie off with a rubber blade (I used a $1.50 glass squeegie from Big Lots)
It took a lot of silicone to properly coat a tarp... maybe 3/4 of a caulking tube. These were heavy-duty canvas tarps, and soaked up the mix like a sponge. I've never used the mineral spirits for cutting silicone, but I would expect white gas to dry much more quickly.
My friend tried copying the technique using regular unleaded gasoline, but the result was less than spectacular, and the scent of gasoline stayed with the tarp for a LoOoOnG time!
I wonder if you could use a small air sprayer to apply the solution evenly and thinly to 1.1 nylon? You could mix the EXACT amount of silicone you wish to use (by weight) with enough solvent to coat the whole piece of fabric, then go at it! A standard HVLP sprayer should be safe to use IF NO IGNITION SOURCE IS PRESENT! I would worry even about an electric air compressor... perhaps use a large can of compressed air?
As stated above, however, you can buy SilNylon without much difficulty! Personally I'd only consider coating my own if I found a specific pattern/print that wasn't available pre-coated...