keeping an eye out for wildlife, help record numbers etc with sites such as ebird and inaturalist
and of course the basics; chemical-free/wildlife friendly gardens, avoid single use plastics
support, volunteer and donate to local nature reserves, local communities, organisations, etc;
if you are from the USA, (and are big bird fans!) join your local national audobon society :)
if you are from the UK, volunteer/donate to your local RSPB