The honey/water before fermenting is called “must”. You will want to add the honey to hot water in a large pot, but make sure the pot is not on the heat while doing this because the honey will fall to the bottom and caramelize (or stir vigorously if you leave it on the heat). Stainless steel or enameled kettles are preferred; aluminum is OK. Do not use iron, nor enameled kettles with cracks in the enamel.
Some mead recipes recommend only heating the must enough to pasteurize it. This is because boiling honey will drive off some of the delicate flavors. Refer to the recipes from the Mead-Lovers Digest or the other references (below).
If scum rises while heating or boiling the must, skim it off. It consists of wax, bee parts, pollen, etc., which don’t help the flavor of the mead.
An alternative preparation method involves the use of “Campden tablets” or “sulfiting” to sterilize the must. If you’re a winemaker, you’ll recognize this method. With the use of Campden tablets, it is not necessary to heat/ boil the must at all first, although some mead-makers do so anyway for the sake of clarity of the final mead. If you use Campden tablets, follow a recipe or instructions for quantity, preparation, delay times before adding yeast, etc. Heating is probably easier than sulfiting for the beginning mead-maker.