Paul

You may choose a colourful style for the custom coupon message, or wrap the message in your own CSS class container.
It’s also possible to hide the default message from Woocommerce so that only your custom coupon message is displayed. 
(the plugin uses inline CSS to hide the default Woocommerce message).
Take a look at the screenshots for the coupon edit screen with the plugin enabled and some examples.
The meta box was implemented using the technique described on this blog post: 
http://wp.smashingmagazine.com/2011/10/04/create-custom-post-meta-boxes-wordpress/
The message styles were generated using this tool: 
http://www.bestcssbuttongenerator.com/

Woocommerce Custom Coupon Message

This plugin adds a meta box to the coupon edit screen where you can make your own customized coupon message.

PT Woo Plugins

Naked Cat Plugins

Marco Almeida | Webdados

With this plugin, you can pass a coupon code via an URL parameter (<code>mcoupon</code> by default) and it will be stored in a cookie for a configurable amount of time.
While the cookie is valid:
<ul>
<li>All the eligible products will have their display price reflect the coupon discount;</li>
<li>A personalized HTML message can be shown on the product page, under the product price (or anywhere else, if you know your way around hooks);</li>
<li>When the client adds the product to the cart, the coupon is automatically applied also;</li>
</ul>
Please note that the coupon can still be applied manually by the user at any time. This will not lock the coupon regular usage.
The support for variable products is experimental and may be moved to a premium add-on in the future.
<h4>Other (premium) plugins</h4>
Already know our other WooCommerce (premium) plugins?
<ul>
<li><a href="https://nakedcatplugins.com/product/shop-as-client-for-woocommerce-pro-add-on/" rel="nofollow ugc">Shop as Client for WooCommerce</a> – Quickly create orders on behalf of your customers</li>
<li><a href="https://nakedcatplugins.com/product/taxonomy-term-and-role-based-discounts-for-woocommerce-pro-add-on/" rel="nofollow ugc">Taxonomy/Term and Role based Discounts for WooCommerce</a> – Easily create bulk discount rules for products based on any taxonomy terms (built-in or custom)</li>
<li><a href="https://nakedcatplugins.com/product/simple-woocommerce-order-approval/" rel="nofollow ugc">Simple WooCommerce Order Approval</a> – The hassle-free solution for WooCommerce order approval before payment</li>
</ul>

Magic URL Coupon for WooCommerce

Simple solution for creating links for WooCommerce with coupons automatically applied. We working and very fast support from the developer. Thank you for that.
Cheers.

Great solution for coupon links

Pass a WooCommerce coupon code via URL and display the product prices as if the coupon has been applied to them. Coupon is automatically added to the  …

Woocommerce Custom Coupon Message vs Magic URL Coupon for WooCommerce