Keywords are not nearly as relevant as they once were because of schemes like keyword stuffing. For meta-keywords don't even bother, Google ignores them.
In content ensure your title tag is focused on the subject and repeat the title tag about twice depending on the size of your post. 500 words - 2x, 800-1000 words - 3x but spread it out to skip redundancy to the reader.
Consider this - when reading your post does the repetition of keywords seem a bit too much? If so, your readers will think the same thing.
I review products and write historical information and I am careful not to refer to the product or item too often. i.e. In a review for the Callaway Mack Daddy 2 wedge I have 800 hundred words and use the term Mack Daddy a number of times and wedge several times. I use internal links to an affiliate directed to Mack Daddy 2 wedges. I only allow myself two outgoing links tied to the keyword Mack Daddy 2 wedges.
Notice I'm discussing long-tail keywords because consider how you search. For the most part people time in multiple words so long-tail keywords in my experience are KEY. And I use images, graphics and a video when available to enhance the whole post, engage the visitor and hopefully lead them to a product click and sale.
Don't use Google keyword planner and find ten keywords and fit them into you blog post. It most likely won't make sense. As I mentioned, stick to long-tail and your targeted audience to focus your information. Title tags are really important in the world of keywords.