Playlisting is never guaranteed, it is up to the Spotify playlist compiler to choose  your song for a particular playlist. 

That said, there are best practices to increase your chances of playlisting. 

1. Ingest your music for delivery to stores 4 to 6 weeks prior to the release date.
2. Claim your artist profile and update it to include fresh artwork, a bio and any other requirements like your links.
3. Pitch your release in the backend of the service to the compilers. If there is a specific playlist you want to be on, then mention that in your pitch.
4. Include info about what you are doing on your end to market your release so the service can see that you are investing in yourself.

I hope that helps you & good luck..