What are the top three SEO strategies?

TOP three timeless and ageless strategies for SEO / Digital Marketing:

Understand your own business niche and target audience. Understand your target audience Behavior. For great SEO results, Dont’ just focus on search engines but focus on your target audience, and giving them information, (If you focused right, this will take care of primary Keyword identification, pagespeed, UI /UX experience, bounce rate).
Develop a good quality, fresh and unique content strategy. This should include Title, Meta Description, H1 and Content for pages/posts and blog. (this will take care of On-page SEO )
Focus on couple of social media platforms, and try to drive targeted traffic to your website from social media. To remain focused, don’t go after too many platforms, just be persistent with right platform related to your business. Also try to get into blog marketing for promoting your blog. (this would take care major part of Off-page strategy)
This should be enough to start the process, just keep it real and always focus on real visitor. (not just search engines)

Let me know via comments if you need answers to specific questions, I will be happy to help.
Disclosure : I co-own BrandNshout .com,a Digital marketing and Branding company.