I need a web developer

I have a website developed on WordPress. No i need to change the theme for it, which must be mobile friendly and ad friendly theme. I have short-listed few themes and you need to pick the best one and change the theme. Then set up ads with a ad network I have registered. I have configured my analytics account and I need help in setting it up correctly. Further, I need to link link social media pages to the website, which I think could be part of the website.

Note: The site is live and having decent traffic. So i need all this to be done without affecting the live site.