Affiliate Marketing Secrets

Hello guys, i want to create a niche website. I don’t know how to use my PRIMARY, SECONDARY and LONG TAIL keywords in:
-URL
-Tittle
-Article
-Footer
–
-other important places i need to put on keywords and how to put them.
And what are header tags and meta tag and how to use these keywords in them?
Please guys help me out, i am stuck 🙁
Please let me know asap
Thank you 🙂