Hi,
All or most of the 2nd foods are the same as the 1st foods, just bigger amounts. So, you should not have introduce them the same way as you did with the 1st foods. You only need to do that with something new. As for juice, babies do not need juice. Formula and water is all they need. With my 1st baby, I would offer water in a sippy cup with his meals and formula in between. I also plan to do with my 5mo old. This also made the transition from bottles to sippy cups at 12/13 mo. really easy with my son. I didn't start giving my son juice until he was close to 2 yrs old and then it was diluted 1/2 to 1/3 with water. My dr always stressed that kids very easily get used to the sweetness of juice and then they refuse their formula/milk/water and you don't want that. So, I would recommend that you don't give juice. They just don't need it. They are getting all of their nutrients from their other food and formula.