You can customize a HomeBay For Sale sign by purchasing a real estate sign rider. Example sign riders might show your phone number, pool, coming soon, price reduced, etc. All of our sign posts have a slot at the top where you can add a rider of your choosing.
With the exception of your phone number, we generally feel sign riders are a waste of money. That said, they are inexpensive so if you feel a particular asset of your home will draw more interest to your property - go for it!
There are lots of vendors who sell various types of signs online to those listing FSBO, those listing without agents and to realtors themselves. Just do a quick Google search for real estate sign riders. You can also find various pre-printed options on Amazon and at local retail stores like Walmart and Home Depot.
If you prefer a custom sign, you can ask a local sign company to print one for you. Local sign companies regularly work with sellers without realtors.