If you begrudge each character of type-in which your system requires, you might like to use the commands 1, 2, 3, 4, ..., 9. They are short for the m command together with a name of a menu subtopic. 1 goes through the first item in the current node's menu; 2 goes through the second item, etc. In the stand-alone reader, 0 goes through the last menu item; this is so you need not count how many entries are there.
If your display supports multiple fonts, colors or underlining, and you are using Emacs's Info mode to read Info files, the third, sixth and ninth menu items have a ‘*’ that stands out, either in color or in some other attribute, such as underline; this makes it easy to see at a glance which number to use for an item.
Some terminals don't support either multiple fonts, colors or underlining. If you need to actually count items, it is better to use m instead, and specify the name, or use <TAB> to quickly move between menu items.