Keywords are the base of any SEO campaign and placing your keywords appropriately not an is not easy task. Here you can find some points about where to add keywords and keyword phrases which may help you;
1. Add Keywords in title tag: title is the best place to add your targeted keywords. The text written inside the title tag displays in search results as your page title. It should be be short and limited to 6-7 words in it. It will be better to add targeted keyword in the beginning of title tag.
2. Add Keywords in URL: Adding your keywords in website URL is also a good idea.
3.Add Keywords in heading tags: Adding keywords in heading tags like H1, H2 and H3 is as beneficial as putting them in page title. Do not use words like: and, for, the, or etc. as they are ignored by search engine spiders. Try to make best possible use of this place.
4.Add Keywords in meta tags: Meta tags are not so important as earlier. Major search engine like google do not consider it but still it is valuable for other search engines like yahoo, msn. So if you are optimizing for yahoo and msn then add your keywords properly.
5.Add Keywords in Alt tags: Search engine spiders are unable to read images or graphics. If you have images in your web page then make sure to include main keyword(s) in the ALT tags, but never over do it as your ranking could be dropped in the result.
6.Add Keywords in anchor text: Anchor text is really an important place to add keywords. Do not create simple internal link with anchor text like “Click Here” or "visit this link" instead of this you can use your keywords relevant to the page. It becomes more important in case of inbound links as it will be regarded as a vote from another site for a particular keyword to your site.