From the perspective of a grandma to 7, my advice is to let your daughter take the lead. Let her know that you are there to support her and do what she would like you to do. Don't offer unasked for advice about anything! And enjoy your grandbaby! They are the best thing ever! I think it can be a bit of an adjustment for those of us who are nurses to stand back and take the role of supporting without falling back to the role of patient teaching, taking charge, etc. Keep in mind, new mom is in charge. If she wants your advice she will ask. I know I'm repeating myself, that's intentional.
