This recipe doesn’t really need measuring & weighing – you just season however much chickpea flour you want to use then whisk in water until it’s a good pouring batter consistency… but if you do want to, these amounts work well:
250g chickpea (gram) flour, 300mls – 400mls water & 1/2 teaspoon salt.
I definitely think it’s worth making the batter the morning or evening before you want to make the pancakes, as it will make them more digestible & give any lumps a chance to break down; just leave it at room temperature covered with a cloth.
To cook, grease a pan (cast iron works best for these but isn’t necessary), pour on some batter & cook on a medium heat for 2-3 minutes on each side.