In general, bundles are featured when they are chosen by admins to be. There’s not much individual developers can do, apart from making sure their games in the bundle are of good quality, but that doesn’t guarantee anything.
If you are looking for spending money to promote the bundle, you can take a look at Become a Sponsor, which explains some more details.
If you are looking for something like the BLM bundle, as far as I’m aware there is no specific steps to create something like that. The only option would be to Contact Support.