For steeping 250g of grain I would use about a litre of water at about 75*C to which I added the grain. Then leave it for about half an hour preferably wrapped up in something to keep the heat in. Then filter off the liquid from the grain using something like a fine kitchen seive, and then sparge (wash) the grain with half to one litre of water at 75*C. Discard the spent grain (mine goes in the composter), then boil the liquid for 10 mins in a stockpot or saucepan to ensure it's sterile before it goes into the wort. Cool the pot or pan in a bowl of cold water before adding the liquid to the wort.
And you don't boil the grain itself because it is likely to extract tannins which you dont want.
Edit:- Sorry just seen
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