Muktzeh Machmat Mitzvato

Items that are designated to be used for a mitzvah on the onset of Shabbat or Yom Tov and can't be used for that mitzvah on Shabbat are considered to be absolutely muktzeh.

Sukkah Decorations

1. Sukkah decorations are designated to be used to beautify the sukkah during the entire holiday of Sukkot and may not be used during Sukkot or Shemini Aseret.
2. If one stipulated before the first day of Yom Tov that one doesn't want to refrain from using the decorations during the onset of any day of Yom Tov the decorations aren't muktzeh.
3. If one just declared that one wants to eat the edible decorations when they fall, that is an ineffective stipulation. Yet, if one declares that one wants to eat the edible decorations at any time of the holiday, the stipulation is effective and the edible decorations aren't muktzeh.
4. Some say that the ashkenazic minhag is not to make a stipulation to use the sukkah decorations that hang from the schach.However, others assume otherwise.
5. If one wants to use the decorations hanging from the walls, one should also make a stipulation just liek the decorations hanging from the schach.
6. If one used a nice smelling flower or fruit as a decoration, one may smell the flower or fruit as long as one doesn't move it. Some say that one may not smell a Hadas if it is used as a decoration.