L.M.
Despite many Dr.'s opinions, the prevailing nutritional wisdom is to not feed grains first. They are more allergenic! Do heed the previous poster's advice. One food a week. Preferably vegggies such as peas, green beans, squash. Very easy to make your own food with organic veggies. He is only 6 mths and since he is getting breast milk he is still getting optimum nutrition.
Slow and steady is the best way to go. Take your time.