The sudden jump you see after 9 is caused by the width of the item number: 2-digits number are wider than 1-digit number. Consequently, the number fully occupies the default tab “cell” and the tab character sets the text position in the next “free” cell, i.e. in cell number 3 insted of number 2 (cell number 1 is the one flushed on the left margin).
Default tab stop is usually set at 1.25cm or ~0.5" which could be filled by your space-digit-digit number depending on the font point size.
To avoid this misaligned presentation you must explicitly set the tab stops in the paragraph style used for the list items.
Built-in styles Numbering x (with x=1 to 9, allowing for 9 different list lay-outs) are provided for this use. You can customise the style with the following procedure:
- display the styles directory as
Format
→ Styles and Formatting
or F11
- right-click on the style name (e.g. Numbering 1) and choose
Modify ...
- select the
Tabs
tab
- set the desired tab stops, taking into account the width of the item number
Note: the same Numbering x can be used for the various levels of your list(s). The indenting level is set with tab characters when the cursor is at the start of the line (before the forst character in the paragraph).
Since you are new to LO, you are encouraged to read the chapter titled Working with styles in the manual (downloadable from http://libreoffice.org).
The anomaly on step 11 is likely due to a typo: there is no tab character after the number, contrary to other lines.
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