We can insert the ladder in two format.
Vertical
Horizontal
We can convert the ladder from vertical to horizontal or horizontal to vertical with help of drawing format (Right top corner in Schematic) .
Schematic > Drawing Properties > Drawing Format > Select The Ladder Defaults > Vertical or Horizontal
Ladder Format

Vertical Ladder 

For vertical ladder we need to check the ladder format and set the ladder in vertical format, after that before going to insert the ladder we have to check the template size.

If the template size  is ( 420W X 297H mm) IEEE standard 
Then we can give the ladder width 120 or 100mm, spacing between rungs 20mm and ladder length, numbers of  rungs we can give manually or we can give required values.

If the template size is (33.43W X 22.39H mm ) JIC standard
Then we can give the ladder width 4.5 or 6mm, spacing between rungs 0.75mm and ladder length, numbers of  rungs we can give manually or we can give required values.

 

Schematic > Inset Ladder > Vertical or Horizontal (Select From Drawing Properties) > Select the 1 Phase > Give Value of Width > Spacing Between Two Rung > Specify Length of Ladder and Number of Rung or We direct insert ( for direct first we have to fill all parameters then just click on drawing space area then how many rung you want you can click on drawing area)