The bundled lulav, hadasim, and aravot are picked up with the right hand, and the etrog with the left, because the three species together are more significant than the etrog and should therefore be picked up with the more prestigious and stronger right hand. If one mistakenly did the reverse, he has still fulfilled the obligation. Some maintain that even lefties should take the lulav in the right hand, because even for lefties, the right hand, which alludes to the divine attribute of kindness, has significance (SA 651:3). This is the kabbalistic practice. Others maintain that since the left hand is dominant and more important for him, a lefty should take the three bundled species in his left hand and the etrog in his right (Rema).
One must hold the four species in the direction they grow: their stems pointing downward and their tips pointing upward. Accordingly, the oketz of the etrog should be at the bottom and the nose on top, for this is how it begins to grow from the tree. If one of the species is reversed, he has not fulfilled the mitzva (Sukka 37b, 45b; SA 651:2).
When one picks up the lulav, its spine should face him. The etrog should be held next to the lulav bundle (SA 651:11). Holding the four species thus, one shakes them in each of the four directions, as well as up and down, as is explained in the next section.
Our Sages ordained reciting a berakha before fulfilling the mitzva: “Blessed are You, Lord our God, King of the Universe, Who has made us holy through His commandments, and has commanded us about taking the lulav” (“al netilat lulav”). So that the berakha is recited just before fulfilling the mitzva, one picks up the four species before reciting the berakha but holds the etrog upside down (oketz up, nose down, a manner that does not fulfill the mitzva). Then one recites the berakha and immediately flips the etrog and shakes the four species. Some hold only the bundled species when reciting the berakha; then, immediately upon concluding the berakha, they pick up the etrog and shake it with the other species (SA 651:5). On the first day, She-heḥeyanu is recited before performing the mitzva (ibid. 6).
It is customary to stand while reciting the berakha and taking the lulav. The berakha covers all the lulavim one might take and shake for the rest of the day (Rema 651:5).
The custom is to take the lulav and recite the berakha right before beginning Hallel (SA 644:1). Some show alacrity by taking the lulav and reciting the berakha in the sukka before going to the synagogue, in order to combine the mitzva of lulav with the mitzva of sukka (Arizal; Shlah). People who pray vatikin (reaching the Amida at sunrise) may not do so, as the time for taking the lulav begins at sunrise.
There must be no barrier between one’s hands and the four species; one who places them in a case or container and then picks up the container does not fulfill the obligation. However, the material used to bundle the three species together is not considered a barrier, as it is meant as an auxiliary to the species. Some people take care to remove rings, but technically rings are not considered barriers, as they cover only a very small part of the hand (SA 651:7).
If one’s hand is bandaged, but his fingers extend beyond the bandages so that he can still hold the species with them, he may, be-di’avad, fulfill the mitzva in this way (Ikarei Hadat 33:25; see Harḥavot). If he cannot hold the four species directly with his fingers, he should fulfill the mitzva using his unbandaged hand only. He should recite the berakha, pick up the bundled species, put them down, and then pick up the etrog. As we have learned, be-di’avad the species may be taken serially.