My method:
Brewing vessel - 5L water dispenser
Coffee - Generally I use african
Filter - Clean generic Chux cloth
Dispensing vessel - As per brewing vessell
Coffee Ratio: I use 10:1 filtered tank water:coffee grounds
Grind Size: I prefer very coarse, bit coarser than plunger
Roast Level: Light roast, pulled as it hits rolling first crack
Immersion time: At this point in time I've tried between 12 and 24 hours.
So in shot, I use a similar method to WotB. I strain with a standard metal strainer to get the bulk out, and then run it through a single chux lined in a colander, then through a double chux back into washed brewing vessel.
The point of my cold brews is to mix 50/50 with milk for delicious iced coffee without sugar, so the extended brewing time might make it a bit muddier in flavour, but that's not so bad for milk based drinks - they taste delicious.
I will try bringing my brew time down to see how it affects it.
I usually do about 3L at a time.
I highly recommend everyone try this method, as it's cheap (generic chux style cloths can be had for 10c each in a 10 pack), and only costs the coffee and a bit of time.