Typically, you'll use 1 part vinegar to 2 parts soy, and as much of the flavourings as you want to achieve the flavour you are after. If this is your first ever time, take 1 small clove of garlic, half an inch of ginger, a handful of coriander leaf and half a medium chili. As you get used to the sauce, you can add or subtract amounts to suit your taste. For a satay-style sauce, add a couple of table spoons of peanut butter. For a Thai-inspired sauce, swap vinegar for lime juice and coriander for basil.