When we started, I gave DS rice cereal around mid-morning and about half hour after a breastfeed. I did it in the morning in case of any allergic reaction, it was a reasonable time of day to get medical help. Also because if it made him cranky, I could deal with it better during the day than being up all night.

I tried one new food every 3-4 days, starting with the rice cereal, then veggies, then fruit, then started to mix and match them.