We do not put up pending signs. The reason traditional brokers do so is because it shows everyone in the neighborhood that they successfully got the home into escrow. This helps the agent get future listings.
But the pending sign is not good for the seller. The reason is, by national statistics, 22% of escrows fall apart. As the seller, you want to continue to collect the contact information from interested buyers and encourage backup offers so you have a strong plan B to defer to if anything happens.
The absence of a pending sign is actually a great example of why selling without a realtor or agent can be sharply to your benefit. The agent is looking out for their best interest. When you are listing FSBO, by contrast, you can look out for your interest.