Well, if what you are talking about is you being a musician wanting to make collabs with other musicians, the most obvious is finding other music channels that you like, trying to be active on their videos so they can interact with you. Get to know them as best as you can (I don't mean as a stalker or harassing them lol). Find out if they are interested in collabs with other artists. See if they would be interested in listening to your music. As opposed to just a regular YT video, music is more personal thus I would think having a personal relationship with another musician is very important before considering collabs with them. After all, you wanna make sure your music is not affected by their personal decisions and vise verse.