Farming describes the act of killing waves of minions and monsters to gather gold and experience. Farming is an essential component of early-game laning, when players try to out-farm the enemy and advance their lane. Early game is the safest time players can farm to attain items and abilities that increase their power.
How to Farm
Gold is granted to the champion that deals the killing shot on any minion or monster. This is known as a 'last hit' and is considered one of the most important skills in League of Legends. Last Hitting will increase a champion's 'creep score' (CS) noted at the far right of champion stats in the tab stats, or top right corner for the player's champion. In the early and mid game, CS can be used as a gauge for comparing how well a player is doing against their respective lane opponent along with KDA. Many champions will use their autoattack (AA) to Last Hit, but several champions, especially AP champs, also have low cost executes or area burst to last hit. Melee minions can take two tower hits and be easy to AA for most ad champions. Caster minions are best to hit once before taking a single tower hit, then AA'ed again for the Last Hit.
This is the main phase for farming. Many champions have abilities which aid farming, either by making it easier to land the killing hit (e.g. granting extra gold, such as or .), or by
It is harder to get CS when your lane is pushed to your tower, since the turret's attacks are stronger than your own, causing it to kill many minions. On the other hand, you can push the lane to the opponent's tower, where they will lose CS. However, this is risky, as it opens the lane up to ganks.
When teamfights begin, gold will come from killing champions, lane minions, and clearing the jungle monster camps. When possible, lanes can still be farmed, though your absence can hurt your team in a teamfight.
Now the game will mainly focus on teamfights, meaning that farming is secondary. Despite this, minion waves will slowly accumulate (usually in side lanes where teamfights are not taking place). These can provide large gold/experience boosts, though as stated before, your absence can potentially hurt your team.
A wave in Summoner's Rift consists from six to seven minions and has value of at least 355.5. As the passive gold gain is 19 gold per 10 seconds this translates that being able to clear each minion in a wave generates roughly double the amount than simply standing around. As wave value slowly increases over time clearing out a merged wave can result in a significant burst of income.
Below there's an updated (Season 8) table chart for the perfect CS at given minutes up until an hour of gameplay. Times are for when the next wave spawns, (e.g. first wave spawns at 1:05, second wave at 1:35, meaning, up until 1:35, only 6 CS are possible). The table does not take super minions or jungle monsters into the calculations.