Switching to a 4 hour routine is a big change and challenge but once your LO get's it she will be fine.
Below is the routine we follow for our days.
It has worked GREAT. A whole lot better then our 3 hour routine.
(We have only recently moved to solids so everything is cerel but will change to others beginning next week. My baby has many allergies to foods.)
8:00 am Wake / 3tbls Cerel / 6 oz Formula
8:30 am Clean up & Get dressed - Mommy & Baby talk time.
9:00 am Baby Einstine Video
9:30 am Play time with a rattle or toy. Read a book.
10:00 am Nap Time
12:00 pm Wake / 3tbls Cerel / 6 oz Formula
12:30 pm Take a walk (or go run errands)
2:00 pm Nap time
4:00 pm Wake / 3tbls Cerel / 6 oz Formula
4:30 pm Play time in room
5:15 pm Family Time (w/ Daddy & Mommy - play and talk)
6:00 pm Short nap (but transitioning out of this one.)
6:45 pm Bath
7:30 pm Cuddle & Read book or listen to music
8:00 pm 8 oz Formula (Put right to bed.)
It is important to make sure you have good wake times. Play together. make sure you child is active so that they do get a little tired and nap well. If you baby goes down for a nap after just eating and sitting around then they have not be stimulated enough to be tired. This causes shorter nap times.