This is something I came across on Quora (that site is so addictive) that I wish I had read about 14 years ago when my daughter was still an infant. A very wise woman writes that every day you are teaching your children something. It just might not be what you think. Read it here. You will thank me for it.
Another piece of advice I wish I'd had in my arsenal but I started to apply it recently even with my older kids. Your breathing influences your child's breathing. So, if you are panicked or upset, it becomes even more difficult to calm your baby down. If your baby is having a fit, try holding your baby close to you while deep breathing as it cues your baby to do the same and deep breathing is the body's way of letting your brain know every thing is A OK.