There are a lot of ways to do it besides stealing other people's content, lol. For example, you can boost your account. Boosted account looks interesting for people, and they will more likely subscribe. Not so long ago I've found out how to buy Instagram followers and used this method. Now I have a nice boosted Instagram account and the number of subscribers grows day by day. And one more thing - work harder. You can't make something good from other people's content.