The most important thing to do before using a bottle is to wash and sterilise it properly.
In addition, always check the temperature of the bottle with the new temperature indicator. It is also necessary to check if the milk flow is adequate, as sometimes if more milk comes out than necessary you can choke your baby, or if the desired amount does not come out, your child will not be feeding properly.
When you give your baby a bottle, try to keep it tilted so that the milk covers the entire surface of the teat and thus avoid swallowing air as much as possible, as this could cause more colic.