Refer a Friend Shortcodes
There are 2 types of shortcodes which you can use to show a referral link to your customers:
The simple shortcode: [WOO_GENS_RAF] will show just a referral link for users that are logged in. Use the url parameter in the shortcode to link to some other page, by default its homepage.
The advanced shortcode comes with social icons and email share ability:
Shortcode is: [WOO_GENS_RAF_ADVANCE guest_text='Please login <a href="login_url">here</a> to access your referral link.' url='http://your_site_url_to_share_leave_empty_for_default']
In general, you want to create a landing page that will have some text explaining benefits of the referral system, then include a shortcode below it. The shortcode will show only for alogged in users, while for guests, you can define which message to show as a parameter like you can see above in shortcode example.
Full Shortcode to replicate My Account Page.
Some custom themes do not use WooCommerce built-in filters, so sometimes you need to add a custom tab with the content. In that case, Refer a friend tab on my account page will not show and you need to use [WOO_GENS_RAF_FULL] shortcode to replicate My Account page.
Contact Form 7 Shortcode
Check this article that explains a usage of a contact form 7.