First, the speaker called losing something a kind of ：art；. She listed several things that have been lost, from daily matters (door keys, mother・s watch) to some further things (names, realms, rivers, a continent). When I read this pome for the first time, I wonder why the speaker ask us to lose something every day and then practice losing farther, faster. Maybe she suggested that we have too many burdens which should be throw out. Recently, I read a book and the author says, ：Some people is burn to keep; some is burn to lose.； I think it is right. When we lose something, we feel painful and anxious. Though it may be no big deal. We should accept the fluster, just like the speaker said. Sometimes we persist too much with what we want to have, like money, position, power, etc.
At the third stanza, the speaker said she lost places and names. Because she mentioned traveling, I make an assumption that the speaker must travel a lot all around the world. When she traveled, she was far away from her home and country. After she went back from traveling, maybe several years later, she found that her country changed. It was not the country she was familiar to. She could not get used to it. So, she said she lost realms, rivers and a continent. She missed them, but she still thought it was not a disaster.
At the last stanza, the speaker lost ：you； (the joking voice, a gesture I love). I think ：you； must be the speaker・s lover. She might break up with her lover. Until finishing this pome, I think all the things the speaker pointed out above are compared with the breakup. Although the speaker repeated ：The art of losing isn・t hard to master； several times, she did not mean it when talking about breaking up with her lover. She might try very hard to forget about her lover, but she still thought about his voice and gestures. So, it is really a disaster.
This pome has a regular rhyme scheme and the repeated line ：The art of losing isn・t hard to master・. I think the speaker wanted to make readers believe that she did not care about the losing. But at the end, we can find out the opposite meaning. And the open and long vowels suggest a long process of losing something. When you read this pome, you will read slowly, not very fast. Because there are not too many explosive sounds. And it also provides a kind of sadness.