Initially you will probably know the significant key-phrases for your business which will become apparent during discussions with us (and if you already have a website that you feel is informative and relevant to your customers, then this can be analysed to provide suggestions of key-phrases that are regularly searched for in Google for example).
Again this will become apparent from the analysis we undertake, tools we use, and resulting discussions with you - but as a general guide bear in mind, “each web page can only be fully optimised for one key-phrase” (or family of key-phrases), so if you have 20 pages to your website then we'll help you identify the 20 key-phrases most likely to bring highest visitor numbers (or best performing) to your website.
If you have 500 product pages spread between 35 categories in an e-commerce environment, then in theory this could support over 500 key-phrases, although these are likely to need to be considered in 35 families of key-phrases.
Either by manually checking each key-phrase in each search engine of interest once a month and filling in the results (e.g. on a spreadsheet) or by signing up for our Search Engine ranking reports service.