When you have negative numbers you can see that numbers in a number line to see what is the greatest and what is the least:
In a number line you put the 0 as the center and to the right you put the possitive numbers and in the left of the 0 the negative numbers, as follow:
Then you can put the numbers you have in a number line:
You get
Purle: -7
Red; -2
Blue: 1
Green: 4
Black: 6
The least number is the number that is more to the left and the greatest is the number taht is more to the right
Then so, the List the integers from least to greatest is:-7, -2, 1, 4, 6