One of the most important things in League of Legends is using totems correctly. You can practice on smurf accounts from happysmurf.com. Most often they are called wards (from the English Ward). Wards provide visibility in a specific area of the map and thereby warn you of impending danger. As a rule, novice players rarely use wards, and even more so rarely buy visible wards, but save money on artifacts and this is a very big mistake.
Correct and timely use of wards allows you to constantly control the map and see all the enemy’s movements. You will always be aware of where the enemy jungler is running and whether the enemy team has started killing the Dragon or Baron. One correctly installed ward can give control of a very large area of the map, which players often run past.
The role of placing wards is primarily assigned to the support and the jungler. The rest of the players use (and even more so buy) wards much less often and, as a rule, only to protect their specific line until the teams start running in a squad. The ward can also be used to have your ally teleport to him using Teleport and help you.
If, for example, your ally teleports to a ward standing in the bushes, then the enemy will not even suspect anything.