As the chapter would indicate, this piece is in simple ternary form. And it was quite difficult to discern due to the ungodly number of non-chord tones.
The A section consists consists of two phrases. The first phrase is four measures long and ends with a PAC in the original key of Bb. The second phrase is very similar to the first phrase except there has been a direct modulation in the dominant key of F and this phrase also ends with a PAC. The next eight bars serve as a development section for the A section. There are some new rhythmic aspects to this part and there is also some more key exploration. After four bars, there is an IAC in the key of C, which is the dominant again of F and then the next four bars work their way back to the key of Bb with a PAC.
After this PAC, the A section starts up again, leading one to think this is rounded binary, but the A section lasts only two measures and is followed by an immediate change of mood into the B section. The key has immediately switched to G major and the feeling has switched from one where the main rhythmic motive is dotted eighth three thirty second notes, to a choral like feeling with only eighth and quarter notes. Schumann does a really good job of deceiving the listener in this part. In the first bar has a I-V-I and in the second bar you think he is going to the I-V-I again but he skips from the one to a IV/V. Anyway, after four bars there is a half cadence. The first two bars of the first phrase are the same as the first phrase, but then the second two measures immediately modulate into Eb major (chromatic mediant!!!!). This serves as the dominant chord for the return back to the A section.
The return of the A section is almost the same the original A section. There are some different little embellishments at time, but all of the cadences are the same. The only difference is that instead of the opening phrase getting interupted by the B section, this time the return of the opening phrase gets to complete itself.