Hi. When you are within 7 days of the sit, you can list the details on the forum under Last-minute sits. The link sets out the details. You can’t link the listing, but you can put enough information so that those on the forum will be able to find it. Hopefully that will help promote it for you.
You can also request that it be promoted on social media. One of the staff members listed under the ‘About’ tab can help you with that.
If you haven’t listed your January sit yet, it’s good to get that done too, rather than waiting until closer to the date.
And welcome 
Enjoy your travels.