Yes, the incline is great advice. When we start out, we don't have the baby in just a onesie, we have them fully dressed so their outfit is slippery. Then we place our hands behind their feet. We don't push them down the track, but our hands act as something for them to push off of, and encourage them to do so. After they have gone down the track a few times like that, we take a flat book and let them kick off of that instead. We move the book forward as soon as the baby makes space for it. After they are comfortable with that, we do the onesie with a book and progress from there. Especially if the room you are in is cold, this might be a good approach. Good luck!