http://minecraft.gamepedia.com/Beacon

I found it simple enough to work out the simplest way of getting what you want, but as Fokkusu said, iron is prolly your best bet as its the simplest to get

Wiki page for beacons.

Using iron or gold is normally the best option for making the pyramid as they're not rare ores.

first, you going to need a several to assloads of iron blocks/gold blocks/emerald blocks/diamond blocks

Then make it like a piramid like when you right click the beacon, you see a piramid.

Well you can put 3x3 one of that block (so that means 9 blocks of iron/gold/emerald/diamond block)

Then put the beacon on top, and boom!!

You can also make it the following patern: 9x9 then 7x7 then 5x5 then 3x3 then beacon