firstly, make sure you baby is ready to take solid food. don't force him too much even if he is older than 6m. he should be able to sit quite properly in the chair.
then you can add vegetables or fruits slowly slowly if he is happy to eat solid food. add pork or chicken or egg yolk by 9-10m. egg white around 1y old.
can't remember very clearly. if you need, give me your email and i will copy you some info. but later, because very busy now.