I tried last summer and it tasted ok. Definitely takes a lot of trial and error I think.
First you should read up on the science of it all,
and especially the funcitonality of each ingredient. You need to know how malt is made from grain, and how yeast feeds off of it. Need to know difference between sweet wort and bitter wort, and how hops are used other than flavor.
Should read up on yeasts a ton. Ale yeasts are different than lager yeasts, which are all different than bread yeasts. Bread yeasts WILL NOT work. Need to know optimal pH for each type of yeast, the rate at which they ferment the sugars, etc.
Obviously there's a lot to it.
I wrote a paper on malt and beer last year (87%

). PM if you want it.