Making your own beer is relatively simple with today’s kits or even from a basic recipe. With kits you have all the ingredients in all the right proportions and if you have a recipe you can measure them out to get the right amount of malt, water, yeast and hops.
So what can go wrong?
The yeast likes to ferment, it wants to eat all that sugar and turn it into alcohol.
That seems simple enough, but other than too much or little sugar and a host of other minor things the main issue now that will affect your beer will be the temperature you brew at. The brew generally likes to be around 20 degrees centigrade. Any higher you may kill the yeast and any lower the yeast might just go to sleep or take a long time to brew (this may make the flavour a little odd). If you get too a higher temperature the fermentation (but not enough to kill the yeast) may take only a day or 2 to brew and it may adversely affect the taste.
Controlling the temperature is not that difficult with one proviso I have found from experience. If you brew during the spring or autumn then generally house conditions are about right. During the winter and colder months you may need a heating mat or jacket for your bucket or barrel. However and this is a biggie; the summer months can be very tricky, most houses in the UK are not are conditioned and if its 25-30 degrees centigrade outside, you house will not be 20 degrees inside. Unless you have a cellar it is probable that you will not be brewing beer during this period. You could always brew an extract batch of beer in the spring and bottle it or a suggestion I have is why not see what the opposition are doing and try your nearest real ale pub is doing. The CAMRA guide will show you where your nearest real ale pub is.