“Position 0” is the new holy grail in organic search rankings. A normal position 1 ranking is great and all, but I’ll take an answer box that features my content (sometimes with an image) over position 1 in almost all cases.
The first thing you must do, before anything else, is determine the keywords that are likely to generate answer boxes. At scale, this is impossible to do without a tool that tracks the SERPs and denotes which keywords have answer boxes. We use STAT for this, but many other tools are now tracking this as well.
Once you understand where answer boxes currently show up, as well as manually review to see where they have the potential to, you can move on to prepping your data to optimize it for an answer box.