6מִצְוָה מִן הַמֻּבְחָר לֶאֱגֹד לוּלָב וַהֲדַס וַעֲרָבָה וְלַעֲשׂוֹת שְׁלָשְׁתָּן אֲגֻדָּה אַחַת. וּכְשֶׁהוּא נוֹטְלָם לָצֵאת בָּהֶן מְבָרֵךְ תְּחִלָּה עַל נְטִילַת לוּלָב הוֹאִיל וְכֻלָּן סְמוּכִין לוֹ וְאַחַר כָּךְ נוֹטֵל הָאֲגֻדָּה הַזֹּאת בִּימִינוֹ וְאֶתְרוֹג בִּשְׂמֹאלוֹ וְנוֹטְלָן דֶּרֶךְ גְּדִילָתָן שֶׁיִּהְיוּ עִקְּרֵיהֶן לְמַטָּה לָאָרֶץ וְרָאשֵׁיהֶן לְמַעְלָה לַאֲוִיר. וְאִם לֹא אֲגָדָן וּנְטָלָן אֶחָד אֶחָד יָצָא וְהוּא שֶׁיִּהְיוּ אַרְבַּעְתָּן מְצוּיִין אֶצְלוֹ. אֲבָל אִם לֹא הָיָה לוֹ אֶלָּא מִין אֶחָד אוֹ שֶׁחָסֵר מִין אֶחָד לֹא יִטּל עַד שֶׁיִּמְצָא הַשְּׁאָר:
The most desirable way of performing the mitzvah is to bind the lulav, myrtle, and willow together, thus making a single, unified entity from the three of them. Before one takes them to perform the mitzvah, he should recite the blessing on the mitzvah of taking the lulav, for all the others are dependent upon it. Afterwards, he takes this bound entity in his right hand and the etrog in his left hand. He must take them as they grow - i.e., their roots below towards the earth, and their heads upward towards the sky. If a person did not bind them together, but rather took them one by one, he has fulfilled his obligation, provided he possesses all four species. However, if he has only one species or he is lacking one species, he should not take them until he acquires the remaining species.