Every man needs to buy himself and his sons the Arba Minim. Any child who knows how to shake the lulav needs to be taught the laws of Arba Minim by his father, who must buy his son the arba minim if he can afford them for his son.
It is a mitzvah to tie the Arba Minim together on Erev Yom Tov. The hadas goes on the right of the lulav and the aravos on the left, making sure that the lulav is at least a tefach higher than the spine of the hadas. Similarly, the hadas must be a little higher than the aravos.
If one did not tie them together, the Arba Minim are still kosher, bedieved. One may not tie them on Yom Tov. The minhag is to make three knots when tying the Arba Minim, one after the next along the lulav.
One may not eat before taking the Arba Minim, and it is proper not to drink before taking them.
The minhag is to make a brachah on the Arba Minim and to wave them in one’s own sukkah, before going to shul.
Women have the minhag to shake the lulav with a brachah, although they do not need to wave it forwards and backwards like men.