In League of Legends, the winning side is usually the one that wins the big team fights. In turn, these fights tend to be won by the team that has the highest networth and the best equipment. Therefore, one of the most important abilities you can develop is the ability to farm.
The 3 Pillars of Farming
To become a better farmer in LoL and MOBA games in general, you need to understand 3 things:
Last Hitting

Last hitting is one of the first skills that you develop as a beginner. Due to the fact that you don’t receive gold when a minion dies unless you land the killing blow, it’s very important that you learn how to do it properly. This may sound easy but in the early portion of each match, called the laning phase, getting last hits can be quite tricky. The reason is easy to understand: both your attack and ability damage is relatively low, so it’s easy to think you have enough damage when in fact you don’t.
You’re not the only one attacking enemy minions. Your own minions and towers do that as well. So you need to time your attacks correctly and use the stop command when appropriate. When you are forced to attack under your own tower, understanding tower damage and minion HP is crucial. Otherwise you won’t know how to take the last hits because your tower deals a lot more damage than you do.
Another problem here is that while you are trying to kill minions, you might get attacked by the enemy champions. So you always need to watch your position and know the limits of your own champion. Understanding specific match-ups is a key component here. If you’re playing Lux against a Yasuo, there are things that you can do and things that you cannot do at each level. One misstep and you risk getting killed.
What Items Work Best

As you gather gold, one thing that you can do to farm faster is to increase your damage, your attack speed, and your sustainability. If you deal more damage per hit, landing last hits becomes much easier. If you attack faster, you can move from camp to camp and take more farm per minute. And if you have HP and mana regen, or perhaps some life steal, you can replenish your health quickly and can go back to base only when buying new items. Otherwise you might be forced to do it frequently and that’s a lot of time you could have spent farming.
When buying items, always buy what you can but aim to build towers a bigger item. Initially, you must focus on just a little bit of sustain and use the rest of your gold to increase your farm potential. For some champions, that means buying more damage. For others it means buying more AP or mana. Depending on the situation, you should always ask yourself: what would accelerate my ability to farm in this game?
Which Locations Are Safe

Once the laning phase is over and you start farming jungle camps in addition to the lanes, you always need to ask yourself: am I safe here?
Some areas are less risky than others. If you’re the team’s Mid or ADC, you should always try to farm there. Other areas are risky and without proper vision, the risk of dying is huge if the opponent knows how to punish your imprudence.
The safety level of a location depends on how many towers you have remaining and how many champions are visible on the map. If you know the location of the enemy champions, you can determine with precision where it’s safe for you to farm and where you might get ganked.
Furthermore, if all of your towers are still standing, it’s much harder for the enemy team to invade your jungle. But if key towers are lost, your map visibility and your protection level will be lower. To some degree, you can compensate for this by having proper ward placement. But you still need to be very careful at all times and watch the minimap every few seconds.