All interviewed experts confirmed that it takes a long time to promote a channel about premalatha leaked video using free methods and in most cases it is inefficient. Therefore, they use such paid promotion methods:

advertising in Telegram channels of similar topics;
targeted advertising.
To promote our channel “Marketing soup” I used both methods. We spent about 26 thousand rubles on both advertising campaigns. A subscriber from advertising in other Telegram channels cost us 46 rubles, a subscriber from targeted advertising – 83 rubles.

Vladimir Senin, Head of Telegram Channel Promotion Department at Netpeak, advises choosing a channel for advertising based on the following criteria:

number of views. This will make it clear how many people will actually see your advertising message;
the ratio of the number of views and the cost of advertising. This will make it clear how much 1 view will cost you;
viewing dynamics. This will make it clear whether the owner of the channel is winding up views. You can check the dynamics of views through Telemetr;
the number of reposts. This will make it clear if the channel owner is catching up with bots instead of real subscribers. Because such channels will almost always have 0 reposts.