乘法口诀倒着写的方法如下：

从9开始倒序

9 × 9 = 81

9 × 8 = 72

9 × 7 = 63

9 × 6 = 54

9 × 5 = 45

9 × 4 = 36

9 × 3 = 27

9 × 2 = 18

9 × 1 = 9

接着是8的乘法口诀

8 × 8 = 64

8 × 7 = 56

8 × 6 = 48

8 × 5 = 40

8 × 4 = 32

8 × 3 = 24

8 × 2 = 16

8 × 1 = 8

然后是7的乘法口诀

7 × 7 = 49

7 × 6 = 42

7 × 5 = 35

7 × 4 = 28

7 × 3 = 21

7 × 2 = 14

7 × 1 = 7

接着是6的乘法口诀

6 × 6 = 36

6 × 5 = 30

6 × 4 = 24

6 × 3 = 18

6 × 2 = 12

6 × 1 = 6

然后是5的乘法口诀

5 × 5 = 25

5 × 4 = 20

5 × 3 = 15

5 × 2 = 10

5 × 1 = 5

接着是4的乘法口诀

4 × 4 = 16

4 × 3 = 12

4 × 2 = 8

4 × 1 = 4

然后是3的乘法口诀

3 × 3 = 9

3 × 2 = 6

3 × 1 = 3

最后是2的乘法口诀

2 × 2 = 4

2 × 1 = 2

最后是1的乘法口诀

1 × 1 = 1

这样，乘法口诀表就倒着写完了。希望这个方法对你有所帮助!