Here's how you can redirect a Wordpress site that uses the Genesis Theme.
1. Login to your Wordpress backend.
2. From your Wordpress dashboard, choose Genesis from the left column and then select Theme Settings.
3. Scroll down until you see the "Header and Footer Scripts" box.
4. Paste your redirect code into this box.
5. Save your changes.
If your Genesis theme came with an existing mobile site, you may also need to go into your general settings and disable that.