Grease pan with butter, & cover lightly with flour. I would advise you use 2 6" pans instead of one so that the cake gets done evenly, and also it saves time.

Preheat your oven, by putting on the oven & setting it at low heat. Assemble all your ingredients on your work top, so you don't forget anything. Place water on heat to boil, this is where you'll get 1cup of boiling water from.

In a bowl, sift flour, cocoa powder, baking powder & baking soda together, add salt & sugar, & stir till properly mixed.

Add eggs, oil & milk to the dry ingredients, & add till properly incorporated, add the vanilla extract & mix thoroughly. Add the boiling water lastly, & mix thoroughly, pour batter into prepared tin & bake for 30-45minutes in the top most part of your oven.

After 30minutes, check for doneness by inserting a skewer in the center of the cake, if it comes out clean then it's done.

Remove from oven once it's done, run a knife round the edges & allow it to cool a bit, then tap pan on the floor or a hard surface to enable the cake to come out easily, & invert on a cooling rack, & allow to cool completely.