title_body: What is the cheapest way to use coffee beans?
upvoted_answer: There are many ways to brew coffee, and several that are on the "inexpensive" end of the spectrum. Your tone sounds like you're not very into coffee, so to that end here are my broad recommendations in that will give you an adequate cup with minimal fuss and expense.
  
  You'll need two basic pieces of equipment:
  
  A grinder. You can buy an inexpensive electric rotary grinder that will be adequate for most purposes -- one example from Amazon. You can also use it for grinding spices or seeds. If you already have one, you will get some odor holdover from one grinding mission to the next, but it's probably fine if you're not very picky. 10-15 quid new, or even cheaper used from a thrift shop etc. You can even mash them up with mortar and pestle.
  
  Some brewing mechanism. The cheapest and simplest are probably drip brew (e.g., pour-over or auto-drip), but I online a few more down below. Your options are manual pour-over (my recommendation) or auto-drip:
  
  
  Manual pour-over. My pick would be a manual pour-over coffee cone, such as this one, a plastic cone holder for like 5 quid. You put the cone over a mug, put in a paper filter, add medium-grind coffee (even as fine as the rotary grinder will give you will be okay), and slowly pour water over the top until brewed.
  Auto-drip. You can find a really cheap auto-drip machine, for instance this one from Amazon, for like 10-15 quid, or even cheaper used. Water goes in the reservoir, paper filter in the basket, add some ground coffee, press the button.
  
  
  That's one solution for decent cup of coffee for as little as 15 quid all in (grinder, coffee cone, paper filters), or perhaps 25-30 for an auto-drip solution.
  
  See also questions tagged as pour-over for how-to information.
  
  Other inexpensive, though somewhat more fussy, preparations include...
  
  
  French press and french-press
  stove-top percolator or moka pot, see also my description of the difference between them and moka
  cold brew; see cold-brew.