There are many wave manipulation techniques in League of Legends, such as freezing or proxy farming, but one of the most popular ones you'll see, especially in some of your high elo games, is the so called Cheater Recall.
This strategy is very simple but highly effective if you have a lane-dominant champion like Darius, Garen, Sett, Illoai, etc. It's a low-risk, high-reward play that allows you to gain a decent advantage early on without almost any counter-play.
Cheater Recall is always performed in the initial three or four minion waves, therefore you have to make sure to know where the enemy jungler is, so that you can avoid any potential early game gank.
First minion wave
When the first minion wave arrives, you have to push slowly, all the while making sure that your wave is always healthier than that of the enemy. Also, always try to keep an eye on where the opposing jungler might be. If you suspect that a gank could be heading your way - you can simply drop a ward to be completely sure.
Second minion wave
When wave number two arrives, the minions should still be somewhere around the center of the lane. After taking the first creep of the second wave, you will probably level up before your opponent does, which will allow you to play more aggressively and will make you a constant threat if the enemy decides to walk up and farm.
Third minion wave
Once the third wave arrives, your job is to kill all the minions as fast as you can. Even if you miss a creep or two, it's not the end of the world because time is what's of the essence here. When you finally clear all the enemy minions - make sure that your creeps land under the enemy tower.
All you have to do now is recall and, even if you missed a couple of minions, you should still have around 400 gold which is more than enough for a decent buy. Once you come back to the lane, you will find yourself in a much more favourable position than your opponent.
This technique allows you to go back to the lane with the advantage of a Long Sword or whatever else you choose to buy, without losing Teleport or some significant farm in the process.