How should I introduce solids to my 5 month old?

i started my 5 month old a few days ago actually. i started him on sweet potatoes and tonight will be squash. i usually give him about 2 tablespoon fulls. he does great on it. right now its mainly practice anyway. he still gets him formula as his main thing through out the day. i feed him solids once a day for now. in a couple weeks i will give dinner and breakfast and then a few more weeks later stick a lunch in there. this is just what we are doing. i suggest squash, sweet potatoes, peas, green beans. any of those are good to start.