Whenever you finish a long rest, you can touch up to 4 non magical objects, imbuing each of them with one of your artificer infusions, turning it into a magic item. You can attune yourself to the item the instant you infuse it, or you can forgo attunement so that someone else can attune the item.
Your infusion remains in an item indefinitely, but when you die, the infusion vanishes after 4 days. The infusion also vanishes if you give up your knowledge of the infusion or you exceed your maximum number of infusions.