It's great to use the opportunities in your baby's day-to-day life to build your attachment. During feeds (bottle or breast), pay attention to your baby's gaze, and take the time to talk to your baby during this time; simply saying what is happening enables them to grow more and more familiar with your voice.
Another good time could be during nappy-changes, where, similar to during feeds, you could narrate, talk to your baby or even sing to them. When you hear your baby begin to make sounds, they may be soothed and comforted by hearing you repeat these back to them.[2]
References:
[1] Bowlby J. (1969). Attachment. Attachment and loss: Vol. 1. Loss. New York: Basic Books.
[2] Lawrence Robinson, Joanna Saisan, M.S.W., Melinda Smith, M.A., and Jeanne Segal, Ph.D.. (2020). Building a Secure Attachment Bond with Your Baby. Available: https://www.helpguide.org/articles/parenting-family/building-a-secure-attachment-bond-with-your-baby.htm.