There will be moments in every baker's experience when they realise they are lacking one crucial ingredient just when s/he is about to start baking. This has happened to me when it came to... flour. It's incredibly hard to find self raising flour here in Korea. Either that or I just don't know enough Korean to distinguish which is the right flour to buy. I can distinguish Cake Flour, Plain Flour and those specially for making Bread. I can get it at a foreign supermarket but just can't justify paying the premium for such a basic ingredient as flour.
So, here's a way to make your own. For every 1 cup of plain flour add 1 1/2 teaspoons of baking powder and 1/2 tsp salt. Whisk the mixture together until well combined and then sift it at least once (twice will be better) and there you go... there's your self raising flour.