The least number should always start off with negatives if there are any. In this case there is so we can start with -2 as our least amount. Next are the small fractions. If you're allowed a calculator, I would use that to find what the decimals will look like for each fraction:
After -2 the next least number is 0 and the next one is the fraction or decimal closest to the number 0 which is 0.4
The next number would be from the fractions we solved earlier. 0.5 and 0.625 would follow 0.4 and then 1.1 and 1.6667(solved for from fraction).
Here is the list:
Hope this helps!