Want to start building your own brews from scratch rather than using someone else's recipe? Then here's a little insight on how to give this a go, but take note, it can be a long and slow process.
With all the different grains and hops, not to mention yeast strains, how on earth do you build a brew that is worth making and is still enjoyable? The easiest and safest way is to use a tried-and-true SMASH recipe (Single Grain And Single Hop) as a base. A SMASH beer can be great for a good drop, but can sometimes lack depth.
So, that means it's time to mix the SMASH up and extend it a little. One option would be to add some more grain so it won't be a single grain any longer, and if you have made a SMASH a few times, you will notice the difference. If you add 300g of medium crystal, for example, you will get some more caramel notes, and the sweetness will be higher after it has fully fermented, meaning a little more flavour and colour change. Remember that flavour descriptors are quite general, so work off your own experience and preferences to decide which malts to use.
After a few brews altering the grain bill, you will be on your way to building a beer to suit your taste. You can also cross-reference with online recipes that have been made up from all corners of the globe, but don't fall into the trap of getting too caught up in the finer details of ingredients like salt additions at this point.
Once you have had a play with malt choices, it's time to think about hop options. You have probably done a lot of brews and understand the three main additions of hops: bittering, aroma and then the dry hop. Keep this in mind when you make your hop selection. For yeast, make sure you refer to the strain profiles of the different yeasts, and choose appropriately because the beer style is largely determined by the yeast strain.
Let's grab a Brewshop recipe and break the ingredients down to see why they are used. The American Pale Ale, for example, has an American origin, so naturally you will want to use American style malts and hops, rather than British. You will not want to use base malts that are overpowering, which is why American Ale Malt is used in this case. The recipe also has some wheat malt for head retention and to make the beer in the glass look the part. Gladiator, a dextrin malt, is used to give some body to the beer, and crystal malt is added for the touch of sweetness you would usually find in a pale ale - not too much though, otherwise it could be heavy on the tongue and come across as a diacetyl bomb.
Falconer's Flight, a blend of American hops, is used to provide classic American flavours. Idaho 7 brings American citrus flavours that also fit in well with the APA style. BRY-97 yeast is used to ferment the brew as it is relatively neutral and lets the American hops shine.
In conclusion, have a reason for why you have chosen ingredients that you did, and obviously your ability to do this will develop with experience and experimentation. After a while, you will get better at building a brew. So when you enter a competition with a beer you have built yourself, it really is yours that did well. Tie that in with home brew competitions to get independent scoring and valuable judging notes, and you are brewing!