Ask HN: How to sell/auction a domain name?

Around 5-6 years ago I purchased a janedoe.com domain name for my sister and have held the registration ever since. She recently changed her surname after she married so no longer has any interest in the domain and is happy to let it expire next month.

However, I've noticed that over the years most of the other janedoe TLDs have been registered, with the .net variation being held by a somewhat popular author.

I'm loath to let what seems to be a somewhat valuable domain just expire, or worse, let it fall into the shadowy world of registrar after-market auctions.

How would HN readers recommend selling this domain without falling foul of looking like a squatter/speculator?