whats the optimum number of kw's to be used in the meta description? and in the meta keywords do they need to be put in order of number of words?
You should optimize a single page for three keywords. Try to write your description as useful and descriptive sentence using your selected keywords. You can use your keywords and key phrase in keywords tag.
Your meta description element should be a unique "relevant" description of that web page. You do not stuff keywords or insert keyword(s) x amount of times into it. Remember, this is the description displayed in search results. Don't you want your description to attrach visitors and not sololy search engines? The keywords meta element isn't used by the major search engines; this was due to abuse. Some search engines do use it, but they are smaller and less popular ones. As the old saying goes "If it doesn't hurt why not?!". I would suggestion keep the keyword(s) and\or phrases to under 15.
The description attribute provides a concise explanation of your web page content.It is also suggested that major search engines consider keywords located in the description attribute when ranking your site. So , you can use your keywords in the description tag but it should not be treated like a meta keyword tag filled only with keywords. You are allowed to use keywords to the maximum but the description should be meaningful and it should be within the limit of allowed characters.
Meta Description ... Don't fill it with keywords ... Meta Description is supposed to be Summary of whole page in 2 Lines .. Meta keywords ... no search engine consider it nymore