I Need content for an email to send out to existing clients to join competetion

I need an email to our existing clients who have bought a specific product category from us and have used it in various events. We need to ask the to enter into our social photo competition and win the award. The client need to like our social media page and send us the images of the items they have used in the events, one of their selected image will be post into our social media page for voting with other competitors. The most likes and comments will be awarded with an expensive prize. The client then can share the link into their pages and medias to get likes and comments.

Our goal is to engage the existing clients to our social media page and reward them. It will boost our social presence and help them to gain more clients and marketing boost for their business too.

The content needs to be clean, attractive and carry the right message to the reader. Past portfolio of similar job would be helpful for selection. content with graphics and html will be bonus.

More details will be provided when job will be agreed.