ByWeight

Assign a weight to a page using the weight field in front matter. The weight must be a non-zero integer. Lighter items float to the top, while heavier items sink to the bottom. Unweighted or zero-weighted pages are placed at the end of the collection.

{{ range .Pages.ByWeight }}
  <h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}

To sort in descending order:

{{ range .Pages.ByWeight.Reverse }}
  <h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}