The most effective supporter perk we've seen is a 'listener shout out,' where you mention your supports at the end of your episode, and in your show notes.
Podcasts can make money through advertising, but typically advertisers are looking for shows with more than 2,000 downloads/listens per episode. A better approach we've seen is to get listeners to support you on Patreon. You can also get them to contribute through PayPal or Buy Me a Coffee. The most effective supporter perk we've seen is a 'listener shout out,' where you mention your supports at the end of your episode, and in your show notes.