3 week old and sleeping

Any advice on how to put 3 week old to sleep without rocking? Everyone is telling me to stop so she doesn't get into a habit and it will be easier to sleep train. First time mom so not sure what to do. For naps and bedtime, we swaddle and put sound machine on but then I rock her a bit and she starts to fall asleep. Once her eyes are closed for a good 5 minutes I put her in the bassinet. I also use the bassinet for both daytime and nighttime sleep? Should I be using a pack n play for daytime or a different room/setting? It doesn't seem like she has her day/night confused. Any advise would be appreciated